SUPERROSIDAE W. S. Judd, D. E. Soltis et P. S. Soltis

Judd, Soltis et Soltis in Amer. J. Bot. 98: E21-E22. Apr 2011


[Saxifragales+Rosidae]


SAXIFRAGALES Bercht. et J. Presl

Berchtold et Presl, Přir. Rostlin: 259. Jan-Apr 1820 [‘Saxifrageae’]

Hamamelidanae Takht., Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 113. 4 Feb 1967; Hamamelididae Takht., Sist. Filog. Cvetk. Rast. [Syst. Phylog. Magnolioph.]: 461. 4 Feb 1967, pro parte; Saxifraganae Reveal in Phytologia 76: 4. 2 Mai 1994

Fossils Archamamelis bivalvis is represented by fossil flowers from the Late Santonian to the Early Campanian of Sweden. The hexamerous or heptamerous flowers have a bicyclic perianth, one series of stamens, one whorl of staminodia, and a gynoecium of three connate carpels. Divisestylus from the Turonian of New Jersey comprises fossil pentamerous flowers with alternipetalous stamens containing striate pollen, an intrastaminal nectariferous disc and two carpels connate at stigmatic and ovary regions; the capsules were apically dehisced and the stomata anomocytic. The Coniacian Lindacarpa pubescens from eastern Siberia is a spherical female inflorescence, the flowers of which having connate sepals and a semi-inferior gynoecium of two connate carpels. Microaltingia apocarpela, from the Turonian of New Jersey, consists of stalked spherical female inflorescences with two basally connate semi-inferior ovaries per flower.

Habit Bisexual, monoecious, andromonoecious, polygamomonoecious, dioecious, androdioecious or polygamodioecious, evergreen or deciduous trees, shrubs or suffrutices (rarely lianas), perennial, biennial or annual herbs. Many representatives are succulent and/or xerophytic with CAM-physiology. Sometimes aquatic.

Vegetative anatomy Roots often diarch. Phellogen ab initio subepidermal, pericyclic or outer-cortical. Secondary lateral growth normal or absent. Tension wood sometimes present. Vessel elements usually with scalariform (sometimes simple, rarely reticulate) perforation plates; lateral pits scalariform, opposite or alternate (rarely reticulate), simple or bordered pits, non-septate. Vestured pits sometimes present. Imperforate tracheary elements fibre tracheids or libriform fibres (sometimes tracheids) with simple or bordered pits, usually non-septate, or absent (sometimes also vasicentric tracheids). Wood rays uniseriate or multiseriate, homocellular or heterocellular, or absent. Axial parenchyma apotracheal diffuse or diffuse-in-aggregates, or paratracheal scanty, vasicentric, unilateral or banded, or absent. Sieve tube plastids Ss or S0 type. Nodes usually 3:3, trilacunar with three leaf traces (sometimes 1:1–3 or ≥5:≥5, unilacunar or multilacunar with one or several traces). Cystoliths sometimes numerous. Secretory cells sometimes with proanthocyanidins and/or ellagitannins. Idioblasts with cyanogenic compounds or druses unusual. Schizolysigenous resinous canals with balsam sometimes abundant. Tanniniferous cells sometimes frequent. Prismatic calciumoxalate crystals, druses or crystal sand often present (rarely elongate crystals or styloids).

Trichomes Hairs unicellular or multicellular, uniseriate or multiseriate, often branched (furcate, stellate, sometimes rarely arachnoid), stalked or unstalked, or absent (sometimes tufted, peltate, clavate or vesicular; often with multicellular apical gland); glandular hairs sometimes frequent, sometimes peltate or lepidote; prickles sometimes abundant on branch epidermis.

Leaves Usually alternate (spiral or distichous; sometimes opposite or verticillate), simple or pinnately or palmately compound, entire or lobed, with usually conduplicate or involute (sometimes flat or curved, rarely plicate, supervolute or convolute) ptyxis (leaves sometimes succulent). Stipules usually absent (sometimes intrapetiolar, rarely pairwise); leaf base usually absent (sometimes sheathing). Colleters sometimes present. Petiole vascular bundle transection arcuate or annular, sometimes with medullary or adaxial bundles. Venation pinnate or palmate, actinodromous, eucamptodromous, brochidodromous or craspedodromous; lateral veins often running out into (glandular) leaf teeth. Stomata usually anomocytic or paracytic (sometimes anisocytic or diacytic, rarely helicocytic), often only on adaxial side of lamina. Cuticular wax crystalloids usually as tubuli (often clustered tubuli [Berberis type, at least in some woody Saxifragales], sometimes as rodlets, threads or platelets), chemically often dominated by nonacosan-10-ol. Domatia as pockets or hair tufts, or absent. Mesophyll and petiolar cortex sometimes with calciumoxalate as druses or single prismatic crystals. Leaf margin usually serrate (sometimes entire, crenate or biserrate); leaf teeth usually rosoid, sometimes platanoid (glandular with cavity, lateral veins almost reaching teeth), fothergilloid (with transparent glandular apex, lateral veins almost reaching teeth) or chloranthoid (with persistent transparent swollen structure, into which high order lateral veins proceed).

Inflorescence Terminal or axillary, racemes, spikes or heads, or raceme-, spike- or head-like, pleio-, di- or monochasia, thyrsoids, fasciculate, panicles, corymbs, racemes or cincinnate (flowers rarely solitary). Floral prophylls (bracteoles) sometimes absent.

Flowers Usually actinomorphic (rarely zygomorphic). Hypanthium sometimes present. Epigyny or half epigyny (sometimes hypogyny). Sepals (two to) four or five (sometimes eight or ten), with imbricate or valvate aestivation, free (sometimes connate at base; sometimes spiral or absent). Petals (two to) four or five (to 13), with imbricate or valvate aestivation, free (sometimes spiral or absent). Nectary and disc absent, or nectariferous disc intrastaminal.

Androecium Stamens (one to) four or five (to more than 100), usually whorled, alternisepalous, or (4–)5+(4–)5, diplostemonous or obdiplostemonous (sometimes spiral). Filaments usually free (rarely connate at base, usually free from tepals (rarely epipetalous). Anthers usually basifixed (usually with filament attached at basal pit; rarely dorsifixed), usually non-versatile, usually tetrasporangiate (rarely disporangiate), usually latrorse (sometimes introrse or extrorse), usually longicidal (dehiscing by longitudinal slits; rarely valvate or with a basal pore or short apical slits). Tapetum secretory. Staminodia usually absent (sometimes antepetalous; female flowers sometimes with staminodia).

Pollen grains Microsporogenesis simultaneous. Pollen grains 2–3-colpate, 2–3-colpor(oid)ate or polypantoporate (sometimes diporate, rately triporate), shed as monads, bicellular at dispersal. Exine tectate or semitectate, with usually columellate (rarely granular) infratectum, perforate, reticulate, rugulate or striate, verrucate, echinulate, spinulate, scabrate or psilate.

Gynoecium Pistil composed of one to 32, usually connate (sometimes free, at least in distal part) carpels, sometimes unsealed distally-ventrally (sometimes spiral); carpel plicate. Ovary inferior or semi-inferior (sometimes superior), unilocular (apocarpy) to quadrilocular. Stylodia two to numerous, free, or absent. Stigmas usually capitate (sometimes decurrent), papillate, Dry or Wet type. Pistillodium usually absent (male flowers sometimes with pistillodium/pistillodia).

Ovules Placentation axile or parietal (sometimes apical or marginal to laminar). Ovules one to more than 100 per carpel, anatropous (sometimes hemianatropous), pendulous, horizontal or ascending, apotropous or epitropous, usually bitegmic (rarely unitegmic), usually crassinucellar (sometimes tenuinucellar). Micropyle usually bistomal, often Z-shaped (zig-zag; rarely exostomal). Nucellar cap sometimes present. Megagametophyte usually monosporous, Polygonum type (rarely disporous, Allium type). Synergids often with a filiform apparatus, rarely haustorial. Endosperm development usually cellular (rarely helobial or nuclear). Endosperm haustorium chalazal or absent. Embryogenesis solanad, caryophyllad or chenopodiad.

Fruit Usually a follicle, a septicidal and/or loculicidal capsule or a nut (sometimes a drupe, a berry, or an assemblage of follicles or nutlets, or a syncarp consisting of follicles or septicidal capsules, rarely a schizocarp with nut-like mericarps).

Seeds Aril usually absent (sometimes funicular aril enclosing seed entirely or partially). Seed coat testal or exotestal (sometimes mesotestal or endotegmic). Exotestal cells often with outer wall (sometimes radial walls) thickened (sometimes partially crushed). Inner pigmented layer often present. Tegmen usually crushed (inner exotegmic layer sometimes pigmented). Endotegmen sometimes with thick sclerotic, cutinized, tanniniferous and/or crystalliferous cell walls. Perisperm usually not developed (sometimes more or less developed). Endosperm copious or sparse, oily, proteinaceous (rarely starchy). Embryo large or small, straight or curved, without chlorophyll. Cotyledons two. Germination phanerocotylar.

Cytology n = 5–37

DNA Insertion present in 18S rDNA. I copy of nuclear gene RPB2 lost. Mitochondrial intron coxII.i3 sometimes lost.

Phytochemistry Flavonols (kaempferol, quercetin, myricetin, apigenin, luteolin, etc.), afzelechin (a flavan-3-ol), methylated and non-methylated flavones, acylated flavonol glycosides, pelargonidin, chalcones, dihydrochalcones, cyanidin, delphinidin, mono- and sesquiterpenes, oleanolic acid derivatives, toxic bufadienolides, Group I carbocyclic iridoids (e.g. daphylloside, monotropein, asperuloside, daphniphylloside), ellagic and gallic acids, bergeniin (C-glycoside of gallic acid), ellagic or gallic acid based hydrolyzable tannins (tellimagrandin I and II etc.), condensed tannins (from procyanidin or prodelphinidin), proanthocyanidins (prodelphinidins), myriophyllin, pyridine alkaloids, glycosides (e.g. paeonol, paeonolide, paeonoside, paeoniflorin, oxypaeoniflorin, benzoylpaeoniflorin and alliflorin), isoleucine-, tyrosine- or valine-derived cyanogenic compounds, coumaric acid, arbutin, acetophenones, galloylic esters, and germacrane-like compounds present. Squalene alkaloids of the daphniphyllin group rare. Saponins not found.

Systematics Saxifragales are sister to Rosidae.

[Peridiscaceae+Medusandra] are sister-group to the remaining Saxifragales.

The remaining Saxifragales have the following more or less strongly supported topology: [[Paeoniaceae+[Altingiaceae+[Hamamelidaceae+[Cercidiphyllaceae+Daphniphyllaceae]]]]+ [[Crassulaceae+[Aphanopetalaceae+[Tetracarpaeaceae+[Haloragaceae+Penthoraceae]]]]+ [[Iteaceae+Pterostemonaceae]+[Grossulariaceae+Saxifragaceae]]]]. It is supported by the potential synapomorphies (Stevens 2001 onwards): floral apex flat to concave early in development; and ovary often inferior to semi-inferior.

The first main clade, with the topology [Paeoniaceae+[Altingiaceae+[Hamamelidaceae+ [Cercidiphyllaceae+Daphniphyllaceae]]]], has the synapomorphies leaves with basically palmate venation; and absence of mitochondral intron coxII.i3. The clade [Altingiaceae+ [Hamamelidaceae+[Cercidiphyllaceae+Daphniphyllaceae]]] is characterized by cuticular wax crystalloids as tubuli, dominated by nonacosan-10-ol; usually racemose inflorescence; absence of pedicel; valvicidal anther with apically protruding connective; and an elongate embryo. Cercidiphyllaceae and Daphniphyllaceae share the potential synapomorphies dioecy; small flowers; absence of petals; and hypogyny.

The second main clade [[Crassulaceae+[Aphanopetalaceae+[Tetracarpaeaceae+[Haloragaceae+Penthoraceae]]]]+[[Iteaceae+Pterostemonaceae]+[Grossulariaceae+Saxifragaceae]]] has the following potential synapomorphies, according to Stevens (2001 onwards): superficial phellogen; vessel elements with simple perforation plates; petiole bundle transection arcuate; cuticular wax crystalloids not as tubuli; ovules apotropous; and calyx persisting as withered. The clade [Crassulaceae+[Aphanopetalaceae+[Tetracarpaeaceae+[Haloragaceae+Penthoraceae]]]] has the synapomorphies: endodermis usually present in stem; nodes 1:1; absence of stipules; and tricolporate pollen grains. The [[Iteaceae+Pterostemonaceae]+[Grossulariaceae+Saxifragaceae]] clade has spiral leaves; presence of hypanthium; antesepalous stamens as many as sepals; ovules numerous per carpel; and a septicidal capsule. Iteaceae and Pterostemonaceae share the features: presence of stipules; one style; axile placentation; sparse endosperm; and presence of flavone-C-glycosides. Likewise, Grossulariaceae and Saxifragaceae share the characters two or three connate carpels; and sometimes helobial endosperm development.

Bayesian consensus tree of Saxifragales based on DNA sequence data (Jian & al. 2008). [Peridiscaceae+Medusandra] are sister group to the remaining Saxifragales with a high bootstrap support. The bootstrap support for Paeonia being sister to the woody Saxifragales was only 59% in analyses by Soltis & al. (2011), whereas the remaining clades are very strongly supported.

ALTINGIACEAE Horan.

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Horaninov, Osnov. Bot.: 271. 1841, nom. cons.

Altingiales Doweld, Ann. Bot. (London) 82: 435. Oct 1998

Genera/species 1/13–15

Distribution Eastern Mediterranean to eastern Himalaya, India, China, Taiwan, Indochina, West Malesia, eastern and northeastern North America, Mexico, Central America.

Fossils Altingiaceae are richly represented by Cenozoic fossils, particularly from the Miocene and the Pliocene. Infructescences of Steinhauera from Eocene layers in Europe resemble those in Liquidambar.

Habit Monoecious, usually deciduous (sometimes evergreen) trees.

Vegetative anatomy Phellogen ab initio superficial. Vessel elements with scalariform perforation plates; lateral pits scalariform or opposite, simple pits. Imperforate tracheary xylem elements ? with bordered pits, non-septate. Wood rays uniseriate or multiseriate, homocellular. Axial parenchyma apotracheal diffuse, or paratracheal scanty, or absent. Sieve tube plastids Ss type. Nodes trilacunar? Schizolysigenous resinous canals with balsam abundant in most tissues. Calciumoxalate crystals?

Trichomes Hairs multicellular, uniseriate or stellate, or absent.

Leaves Alternate (spiral), simple, usually palmately lobed (rarely entire), with flat-conduplicate ptyxis. Stipules (intra?)petiolar, small, usually caducous; leaf sheath absent. Petiole vascular bundle transection annular; petiole with medullary bundles. Venation palmate, usually actinodromous (sometimes camptodromous). Stomata paracytic. Cuticular wax crystalloids as tubuli? Domatia as pockets or hair tufts. Leaf margin usually serrate (rarely entire); leaf teeth platanoid (glandular with cavity).

Inflorescence Terminal, cymose (condensed panicles); male inflorescences capitula in spike- or raceme-like partial inflorescences; female inflorescences globular, with intercarpellary outgrowths corresponding to sterile flowers.

Flowers Actinomorphic, small. Epigyny? Tepals absent (or as tiny rudimentary scales?). Nectary absent. Disc absent.

Androecium Stamens four to ten. Filaments free. Anthers basifixed, non-versatile, tetrasporangiate, latrorse, longicidal (dehiscing by longitudinal valves or slits). Tapetum secretory. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains triporate to polypantoporate, shed as monads, bicellular at dispersal. Exine semitectate, with columellate infratectum, finely reticulate.

Gynoecium Pistil composed of two connate carpels; carpels with various orientation (sometimes transversely orientated), unsealed, only lower carpels fertile. Ovary inferior?, bilocular. Style absent. Stigmas much decurrent, with multicellular appendages (sometimes unicellular papillae?), Dry type. Pistillodium absent.

Ovules Placentation axile. Ovules c. 20 to 47 (only lower ovules fertile) per carpel, anatropous?, horizontal, apotropous, bitegmic, crassinucellar. Micropyle usually bistomal? (sometimes endostomal). Outer integument approx. two cell layers thick. Inner integument approx. five cell layers thick. Megagametophyte monosporous, Polygonum type. Endosperm development ab initio nuclear. Endosperm haustoria? Embryogenesis?

Fruit A septicidal (and occasionally loculicidal) lignified capsules (sometimes more or less connate). Endocarp cells thickened, transversely elongate relative to longitudinal axis of fruit.

Seeds Aril absent. Seed winged (wings developed from elongation of integuments surrounding micropyle). Seed coat testal (or exotegmic?). Exotestal cell walls often lignified. Mesotestal cells more or less sclerotized. Endotestal cells oblong, with lignified walls. Exotegmen well developed? Endotegmen? Perisperm not developed. Endosperm poorly developed. Embryo long, straight, chlorophyll? Cotyledons two, flattened. Germination phanerocotylar.

Cytology n = 15, 16 – Polyploidy occurring.

DNA Mitochondrial intron coxII.i3 lost.

Phytochemistry Flavonols (quercetin, myricetin), cyanidin, Group I carbocyclic iridoids (daphylloside, monotropein), ellagic acid, tannins, and proanthocyanidins (prodelphinidins) present. Cyanogenic compounds not found.

Use Ornamental plants, timber, carpentry, medicinal plants (gum from Liquidambar orientalis).

Systematics Liquidambar (13–15; eastern Mediterranean [the Aegean Islands, Rhodos, Cyprus, southern Turkey], Bhutan, Assam, India, China, Taiwan, Indochina, West Malesia, eastern and northeastern North America, eastern and southern Mexico, Central America southwards to Costa Rica).

A basal branching of Liquidambar comprises one East Asiatic clade and one European-American clade (Ickert-Bond & Wen 2006).

The Cretaceous fossils Lindacarpa, Microaltingia and Vilyungia were rejected by Friis & al. (2011) as belonging in Altingiaceae. They were instead considered “unassigned Saxifragales”.

APHANOPETALACEAE Doweld

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Doweld, Tent. Syst. Plant. Vasc.: xxvii. 23 Dec 2001

Genera/species 1/2

Distribution Western and southeastern Australia.

Fossils Unknown.

Habit Bisexual, evergreen climbing shrub or liana. Lenticels elevated and prominent.

Vegetative anatomy Phellogen ab initio superficial. Endodermis distinctly delimited, as innermost cortical layer. Pericyclic fibres absent. Vessel elements with scalariform perforation plates; lateral pits?, bordered pits. Imperforate tracheary xylem elements fibre tracheids with bordered pits?, non-septate. Wood rays uniseriate homocellular or multiseriate heterocellular. Axial parenchyma apotracheal diffuse, or paratracheal scanty. Ray parenchyma cells starchy. Sieve tube plastids Ss type? Nodes 1:1(–2), unilacunar with one bifid leaf trace. Crystals?

Trichomes Hairs absent.

Leaves Usually opposite (rarely verticillate), simple, entire, with ? ptyxis. Stipules? present on both sides of nodes, modified into tooth-like colleters; leaf sheath absent. Petiole bundle transection arcuate?; petiole with usually three (rarely one) vascular bundles. Venation pinnate. Stomata anomocytic. Cuticular waxes? Leaf margin entire or serrate; leaf teeth one-veined, salicoid, without glands.

Inflorescence Axillary, paniculate cymose, or flowers solitary.

Flowers Actinomorphic. Hypanthium present, short. Half epigyny. Sepals four (or five), with imbricate aestivation, persistent, largely free. Petals four (or five), rudimentary and visible only as young, free, or absent. Tepals connate at base into tube. Nectary? Disc absent.

Androecium Stamens usually eight (sometimes ten). Filaments connate at base into a tube, adnate to tetals (epitepalous). Anthers elongate, almost basifixed, non-versatile, tetrasporangiate, latrorse-introrse, longicidal (dehiscing by longitudinal slits); connective prolonged. Tapetum secretory? Staminodia absent.

Pollen grains Microsporogenesis simultaneous? Pollen grains tricolporate, shed as monads, bicellular at dispersal. Exine tectate, with columellate? infratectum, rugulate-stellate.

Gynoecium Pistil composed of four connate antepetalous carpels. Ovary semi-inferior, quadrilocular. Style single, quadrilobate, with four stylar canals. Stigma papillate, type? Pistillodium?

Ovules Placentation apical-axile. Ovule usually one (rarely two) per carpel, anatropous, pendulous, epitropous, bitegmic, crassinucellar. Funicle long, thick. Micropyle bistomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Parietal tissue? Megagametophyte monosporous, Polygonum type. Endosperm development? Endosperm haustoria? Embryogenesis?

Fruit A one-seeded nut with persistent and accrescent calyx.

Seeds Aril absent. Seed reniform or hippocrepomorphic, often winged or with long hairs. Testa? Tegmen? Perisperm not developed. Endosperm copious?, fleshy. Embryo curved, chlorophyll? Cotyledons two. Germination?

Cytology n = ?

DNA

Phytochemistry Unknown.

Use Ornamental plants (Aphanopetalum resinosum).

Systematics Aphanopetalum (2; A. clematideum: westernmost Western Australia; A. resinosum: warm-temperate parts of southern Queensland and New South Wales).

Aphanopetalum is sister to the clade [Tetracarpaeaceae+[Haloragaceae+Penthoraceae]].

CERCIDIPHYLLACEAE Engl.

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Engler, Syllabus, ed. 5: 126. Jul 1907, nom. cons.

Cercidiphyllales Hu ex Reveal in Phytologia 74: 174. 25 Mar 1993

Genera/species 1/1–2

Distribution: China, Japan.

Fossils Reports of Cercidiphyllaceae from the Cretaceous, based on leaves and fruits, are ambiguous. On the other hand, the Paleocene Joffrea speirsiae from Alberta (Canada) has an elongated receptacle and a bicarpellate pistil with the adaxial sutures directed against one another, resembling extant Cercidiphyllaceae. Similar fossils are known from the Maastrichtian of western North America. Fossilized leaves and inflorescences (with flowers possessing sometimes pentamerous perianth) indicate that Cercidiphyllum was widely distributed in the Northern Hemisphere during the Cenozoic.

Habit Usually dioecious (rarely monoecious), deciduous trees with very distinct difference between long and short shoots.

Vegetative anatomy Phellogen ab initio outer-cortical. Primary medullary rays narrow. Primary stem with continuous vascular cylinder. Vessel elements with scalariform perforation plates; lateral pits opposite to scalariform, simple and/or bordered pits. Imperforate tracheary xylem elements fibre tracheids with bordered pits, non-septate. Wood rays biseriate with uniseriate ends, heterocellular. Axial parenchyma apotracheal diffuse?, or paratracheal scanty or banded, or absent. Tyloses abundant. Sieve tube plastids Ss type. Nodes on short shoots unilacunar (with one leaf trace?), on long shoots trilacunar (with three traces?). Parenchyma with prismatic calciumoxalate crystals.

Trichomes Hairs usually absent.

Leaves Usually opposite (rarely verticillate) on long shoots, a few alternate on short shoots, simple, entire, with involute ptyxis. Stipules adaxial-petiolar (intrapetiolar), small, caducous; leaf sheath absent. Petiole vascular bundles? Leaf bases on long shoots cuneate, on short shoots cordate. Venation palmate brochidodromous. Stomata anomocytic. Cuticular wax crystalloids as clustered tubuli (Berberis type), chemically dominated by nonacosan-10-ol. Mesophyll and petiolar cortex with calciumoxalate as druses or single prismatic crystals. Leaf margin on long shoots entire to finely serrate, on short shoots crenate; leaf teeth chloranthoid (with persistent transparent swollen structure, into which higher order lateral veins proceed).

Inflorescence Terminal, dense, few-flowered on sympodial short shoots; female inflorescences capitate pseudanthia, with two to eight flowers, often surrounded by involucre of sepaloid bracts; male inflorescences raceme-like, short, with (lower flowers) or without (upper flowers) bracts. Prophyll adaxial.

Flowers At least male flowers zygomorphic (with stamens on abaxial side). Hypogyny? Tepals absent. Nectary absent. Disc absent.

Androecium Stamens 16–35, in fascicles (flowers?) each with one to 13 stamens. Each staminal fascicle (flower?) subtended by a single bract. Filaments long, thin, free. Anthers basifixed, non-versatile, tetrasporangiate, latrorse, longicidal (dehiscing by longitudinal slits); connective somewhat prolonged at apex. Tapetum secretory, with binucleate cells. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolpate, shed as monads, bicellular at dispersal. Exine tectate, with columellate infratectum, perforate or finely reticulate, beset with supratectal verrucae.

Gynoecium Pistil composed of one carpel (monocarpellate); carpel plicate, somewhat stipitate, with abaxial ventral suture. Ovary superior?, unilocular (apocarpy). Stylodium long. Stigma decurrent its entire length, papillate, Dry type. Pistillodium absent.

Ovules Placentation laminal-lateral (marginal). Ovules c. 15 to c. 30 per carpel, anatropous, pendulous, apotropous, bitegmic, crassinucellar. Micropyle bistomal. Outer integument four or five cell layers thick. Inner integument two or three cell layers thick. Chalazal end elongating into a wing-like structure during maturation. Megagametophyte monosporous, Polygonum type. Endosperm development ab initio cellular. Endosperm haustoria? Embryogenesis caryophyllad.

Fruit A follicle. Groups of adjacent follicles forming a syncarp (multifolliculus).

Seeds Aril absent. Seed small, with a chalazal wing-like appendage with hairpin-like vascular bundle. Seed coat testal. Testa indistinct. Exotestal cells enlarged, somewhat thickened. Tegmen tanniniferous, degenerating. Perisperm not developed. Endosperm poorly developed, oily, with one large suspensor cell. Embryo large, straight, well differentiated, without chlorophyll. Cotyledons two. Germination phanerocotylar.

Cytology n = 19

DNA Mitochondrial intron coxII.i3 lost.

Phytochemistry Flavonols (kaempferol, quercetin), cyanidin, chalcones, dihydrochalcones, ellagic acid, and tannins present. Cyanogenic compounds and saponins not found.

Use Ornamental plants, carpentry.

Systematics Cercidiphyllum (1–2; C. japonicum: Honshu, Shikoku, Kyushu and Hokkaido in Japan; C. magnificum: Hubei, Sichuan and Shaanxi in China).

Cercidiphyllum are probably sister to Daphniphyllum (Daphniphyllaceae).

CRASSULACEAE J. St.-Hil.

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Saint-Hilaire, Expos. Fam. Nat. 2: 123. Feb-Apr 1805 [‘Crassuleae’], nom. cons.

Sempervivaceae Juss., Gen. Plant.: 207. 4 Aug 1789 [‘Sempervivae’]; Sedaceae Roussel, Fl. Calvados, ed. 2: 291. 1806 [’Sedoideae’]; Cotyledonaceae Martinov, Tekhno-Bot. Slovar: 168. 3 Aug 1820 [‘Cotyledones’]; Rhodiolaceae Martinov, Tekhno-Bot. Slovar: 546. 3 Aug 1820 [‘Rhodioleae’]; Sempervivales Juss. ex Bercht. et J. Presl, Přir. Rostlin: 238. Jan-Apr 1820 [‘Semperviveae’]; Tillaeaceae Martinov, Tekhno-Bot. Slovar: 635. 3 Aug 1820; Sedales Reichb., Bot. Damen: 462. 1828 [’Sediflorae’]; Crassulales Link, Handbuch 2: 18. 4-11 Jul 1829 [’Crassulaceae’]; Sedineae Rchb., Deutsch. Bot. Herb.-Buch: lxiii. Jul 1841 [‘Sediflorae’]; Crassulopsida Brongn., Enum. Plant. Mus. Paris: xxviii, 106. 12 Aug 1843 [’Crassulineae’]

Genera/species c 30/1.400–1.450

Distribution Temperate, subtropical and alpine regions on both hemispheres, with their largest diversity in Mexico and southern Africa.

Fossils Uncertain.

Habit Usually bisexual (rarely unisexual), usually perennial (rarely annual or biennial) herbs, suffrutices or evergreen shrubs (rarely trees or epiphytes). Leaf succulents. Usually xerophytes. Rarely aquatic (i.a. Crassula aquatica). Many species produce adventitious roots from broken leaves; some species form bulbils along leaf margins or in inflorescences.

Vegetative anatomy Roots usually fibrous. CAM physiology frequently present; acid metabolism often Crassulaceae type (via isocitrate). Mycorrhiza absent. Phellogen ab initio usually subepidermal (sometimes cortical). Young stem with separate vascular bundles. Cortical and/or medullary vascular bundles present or absent. Endodermis present or absent. Secondary lateral growth usually normal (rarely anomalous). Vessel elements (usually short) usually with simple (in Sedum rarely reticulate) perforation plates; lateral pits scalariform(-reticulate) or alternate, simple pits? Imperforate tracheary xylem elements libriform fibres with simple pits, non-septate, or absent. Wood rays absent. Axial parenchyma usually paratracheal scanty vasicentric. Wood elements often storied. Phloem little developed. Sieve tube plastids S0 type, without starch or protein inclusions. Nodes 1:1, 1:2, 1:3, unilacunar with one to three leaf traces, or ≥3:≥3, trilacunar to multilacunar with several traces. Cork tissue usually without resin. Prismatic crystals or crystal sand present or absent.

Trichomes Hairs unicellular or multicellular, usually uniseriate or biseriate (sometimes furcate, stellate, rarely arachnoid), vesicular hairs frequent; glandular hairs often frequent.

Leaves Usually alternate (spiral) or opposite (in some species of Sedum verticillate), usually simple (rarely pinnately or palmately compound), usually entire (rarely lobed), often round in cross-section, usually succulent, with curved to flat ptyxis. Stipules and leaf sheath absent. Petiole vascular bundle transection arcuate. Venation pinnate or palmate, camptodromous or reticulate. Stomata usually anisocytic (rarely helicocytic with second ring of subsidiary cells outside anisocytic cell configuration), often on both laminal surfaces (amphistomatic). Cuticular wax crystalloids as platelets, rodlets (sometimes as elongated rosettes, sometimes longitudinally furrowed), threads or lobate to smooth platelets, chemically characterized by high amounts of triterpenoids. Hydathodes abundant. Epidermis often with mucilage cells. Lamina usually without palisade tissue. Mesophyll in succulent leaves often with outer chlorenchyma grading into inner chlorophyll-poor water storage parenchyma. Tanniniferous cells abundant. Crystals and druses frequent (sometimes crystal sand). Leaf margin serrate, crenate or entire.

Inflorescence Usually terminal (rarely axillary), thyrsoid, pleio-, di- or monochasium (cincinnus or corymb; rarely panicle, raceme- or spike-like). Extrafloral nectaries rarely (Adromischus) present.

Flowers Usually actinomorphic (rarely zygomorphic). Hypanthium present. Hypogyny to half epigyny. Sepals (three to) five (to 32), with imbricate aestivation, free or connate at base. Petals (three to) five (to 32), with quincuncial, cochlear, contorted, imbricate or valvate aestivation, free or entirely or partially connate into a tube. Nectaries as abaxial usually scale-like or elongate (in ’Monanthes’ petaloid) outgrowths from carpel bases. Disc absent.

Androecium Stamens usually twice as many (sometimes as many) as petals, usually in two whorls, obdiplostemonous (sometimes a single whorl, antesepalous). Filaments usually free (sometimes connate at base), free from or (when sympetalous) adnate to corolla tube (antepetalous stamens inserted somewhat higher up than antesepalous stamens). Anthers basifixed, non-versatile, tetrasporangiate, usually latrorse (rarely somewhat introrse), longicidal (dehiscing by longitudinal slits). Tapetum secretory, with uninucleate cells. Staminodia usually absent (female flowers often with staminodia).

Pollen grains Microsporogenesis simultaneous. Pollen grains usually tricolporate, shed as monads, bicellular at dispersal. Exine tectate or semitectate, with columellate infratectum, reticulate or rugulate, usually with striae.

Gynoecium Carpels (three to) five to ten (to 32), as many as petals, antepetalous, usually free (sometimes connate at base; in Crassula pageae entirely connate), sometimes stipitate. Ovary superior to semi-inferior, unilocular (apocarpy). Stylodia usually short (style rarely single, branched), usually with abaxial nectariferous scale at base (secreting nectar through stomata). Stigmas small, usually apical, capitate to punctate, papillate, usually Dry (sometimes Wet) type. Pistillodia usually absent (male flowers often with pistillodia).

Ovules Placentation usually marginal to laminar (rarely parietal). Ovule one to usually numerous per carpel, anatropous, pendulous to horizontal, bitegmic, crassinucellar or (in Crassuloideae) tenuinucellar. Micropyle usually bistomal (sometimes exostomal or endostomal). Outer integument approx. two cell layers thick. Inner integument two or three cell layers thick. Nucellar cap approx. four cell layers thick. Hyponucellus (part of megasporangium present below developing megagametophyte) strongly enlarged during development (Sedum and Crassula types of megasporangium). Megasporangial apex sometimes extending beyond outer integument; apical cell seemingly subpalisade. Megasporocyte usually single (archespore sometimes multicellular). Megaspore haustoria present in some species. Megagametophyte usually monosporous, Polygonum type (in Hylotelephium disporous, Allium type). Synergids sometimes haustorial (synergidal haustoria present). Antipodal cells sometimes proliferating and haustorial. Micropylar suspensor haustorium often well developed. Endosperm development usually cellular (rarely helobial or nuclear; endosperm in e.g. Crassula aquatica reduced with chalazal chamber of bicellular stage not dividing but becoming haustorial). Endosperm haustorium chalazal. Embryogenesis caryophyllad.

Fruit Usually an assemblage of follicles (rarely nutlets or a capsule; in Diamorpha secondarily fused into a syncarp).

Seeds Aril absent. Testa usually with papillae or longitudinal ridges. Outer wall of exotestal cells thickened. Two layers crushed. Inner exotegmic layer pigmented. Perisperm not developed. Endosperm sparse (thin layer surrounding hypocotyl), oily, or absent. Suspensor uniseriate; basal suspensor cell with hypha-like haustorial branches. Embryo small, straight, elongate, without chlorophyll. Plumule absent. Cotyledons two, fleshy. Germination phanerocotylar.

Cytology n = 4-≥22 – Karyologically very variable; even the base number varying at least between x = 5 and x = 37 (especially in Sedum; S. suaveolens has the highest haploid chromosome number among angiosperms: n = 320, 40x). Polyploidy and aneuploidy frequently occurring.

DNA

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), methylated and non-methylated flavones, acylated flavonol glycosides, cyanidin, red anthocyanins (frequent, also in roots), toxic bufadienolides and similar substances (in Tylecodon, Cotyledon and Kalanchoe), gallic acid, proanthocyanidins (prodelphinidins), non-hydrolyzable tannins, pyrridine alkaloids and other alkaloids, cyanogenic compounds, arbutin, acetophenones, galloylic esters and isocitrate present. Sedoheptulose main reserve sugar. Aluminium accumulated in some species. Ellagic acid and hydrolyzable tannins not found. Cyanogenesis via isoleucine or valine.

Use Ornamental plants, medicinal plants.

Systematics Crassulaceae are sister-group to the clade [Aphanopetalaceae+[Tetracarpaeaceae+[Haloragaceae+Penthoraceae]]].

A possible topology is [Crassuloideae+[Kalanchoideae+Sempervivoideae]].

Crassuloideae Burnett, Outline Bot.: 736, 1092, 1131. Feb 1835 [’Crassulidae’]

2/c 200. Crassula (c 200; almost cosmopolitan), Hypagophytum (1; H. abyssinicum; Ethiopia). – Subcosmopolitan. The Tillaea clade of Crassulais nearly cosmopolitan and the only indigenous clade of Crassulaceae in Australia. Leaves opposite. Leaf margin with hydathodes. Sepals four (or five). Petals four (or five. Stamens four (or five). Anthers somewhat introrse. Carpels three to nine. Median carpel in Tillaea clade abaxial. Ovules tenuinucellar. Parietal tissue absent. Archespore sometimes multicellular. Megasporangial epidermal cells often large. First division of micropylar endosperm cell horizontal. Follicles dehiscing by apical pore. Testal cells often with a single papilla and sinuous anticlinal walls. Tegmen absent. x = 7, 8.

[Kalanchoideae+Sempervivoideae]

Leaf margin usually with only one (sub)apical hydathode. Anthers introrse only in early bud. Placentae sometimes lobed. Parietal tissue present, one to four cell layers thick. First division of micropylar endosperm cell vertical. Seeds costate.

Kalanchoideae A. Berger in Engler et Prantl, Nat. Pflanzenfam., ed. 2, 18a: 383. 3 Mai 1930

4/c 225. Adromischus (c 30; southern Africa), Kalanchoe (c 140; eastern and southern Africa, Madagascar), Tylecodon (c 45; southern Africa), Cotyledon (9; eastern and southern Africa, the Arabian Peninsula). – Africa, the Arabian Peninsula, with their highest diversity in the Karroo in South Africa. Shrubs or suffrutices (sometimes small trees). Calciumoxalate present as crystal sand. Petals connate. Anther connective with spherical prolongation. Megasporangial epidermal cells sometimes large. Seeds with four to six costae and micropylar corona. x = 9, 17 (18). Toxic bufadienolides (cardiac glycosides) present.

Sempervivoideae Arn., Botany: 112. 9 Mar 1832 [‘Sempervivae’]

c 25/970–1.000. Usually perennial (sometimes annual) herbs, shrubs, or suffrutices. Hylotelephium clade Sinocrassula (7; Himalayas, southwestern China; incl. Kungia?), Kungia (2; China; in Sinocrassula?), Meterostachys (1; M. sikokiana; southern Korean Peninsula, southern Japan), Orostachys (12; Europe, temperate Asia), Hylotelephium (27–33; temperate regions on the Northern Hemisphere), Perrierosedum (1; P. madagascariense; Madagascar). – Umbiliceae Meisn., Plant. Vasc. Gen.: Tab. Diagn. 134, Comm. 98. 8-14 Apr 1838. Umbilicus (14; Europe, the Mediterranean and eastwards to Iran, North and East African mountains), Pseudosedum (1–12; Central Asia), Rhodiola (60–90; alpine and mountain areas on the Northern Hemisphere), Phedimus (c 20; Europe, temperate Asia). – Semperviveae Dumort., Fl. Belg.: 85. 1827. Sempervivum (63; Europe, the Mediterranean, Morocco, western Asia), Petrosedum (7; Europe, the Mediterranean, temperate Asia, North America). – Sedeae Fr., Fl. Scan.: 97. 1835. Aeonium (c 35; Macaronesia, the Mediterranean and southwards to Tanzania, the Arabian Peninsula), Pistorinia (2; western Mediterranean), Rosularia (27; Europe, the Mediterranean, North Africa, Turkey and eastwards Central Asia and Himalayas), Prometheum (8; Europe, Asia), Sedella (3–4; southern Oregon, California), Dudleya (c 45; southwestern North America, northwestern Mexico), ’Sedum’ (c 420; non-monophyletic), Villadia (c 20; Texas, Mexico, Central America, northwestern South America to Peru), Lenophyllum (5–6; Texas, northeastern Mexico), Graptopetalum (12–19; Arizona, Mexico), Thompsonella (3; Mexico), Echeveria (c 150; tropical and subtropical America, with their highest diversity in Mexico), Pachyphytum (12; Mexico). – Temperate, subtropical and alpine regions on the Northern Hemisphere and southwards to Madagascar and Peru. Leaves usually alternate (spiral; sometimes opposite). Flowers tetramerous to 32-merous. Petals usually free (rarely connate). Carpels three to 32. Megasporangium prolonged, with central vascular bundle. Follicle in Sedum rarely with abaxial dehiscence. Seeds with more than six costae. Micropylar suspensor cell vertically dividing. Suspensor often with compound plasmodesmata. x = 5 or more. Pyrrolidine and piperidine alkaloids often present. Nonhydrolyzable tannins not found. – All species of Echeveria appear to be interfertile. The highly polyphyletic ‘Sedum’ occurs in five of the seven main clades of Sempervivoideae.

Cladogram 1 of Crassulaceae based on DNA sequence (matK) data (Mort & al. 2001).

Cladogram 2 of Crassulaceae pro parte based on DNA (matK) data (Mort & al. 2001).

DAPHNIPHYLLACEAE Müll.-Arg.

( Back to Saxifragales )

Müller Argau in A.-P. de Candolle et A. L. P. P. de Candolle, Prodr. 16(1): 1. med Nov 1869, nom. cons.

Daphniphyllales Pulle ex Cronquist, Integr. Syst. Class. Fl. Pl.: 178. 10 Aug 1981; Daphniphyllanae Takht., Divers. Classif. Fl. Pl.: 140. 24 Apr 1997

Genera/species 1/c 30

Distribution Southwestern India, Sri Lanka, Himalaya, southern Tibet, Assam, East Asia to Taiwan, the Korean Peninsula and Japan, Southeast Asia, Malesia, New Guinea, the Solomon Islands, tropical Australia, with their largest diversity in Yunnan.

Fossils Unknown.

Habit Usually dioecious (rarely polygamodioecious), evergreen trees or shrubs. Branches provided with numerous lenticels.

Vegetative anatomy Phellogen? Medulla often septated by diaphragms. Pericyclic fibres absent. Vessel elements with scalariform perforation plates; lateral pits opposite to scalariform, simple and/or bordered pits, non-septate. Imperforate tracheary xylem elements tracheids with bordered pits, non-septate? Wood rays uniseriate or multiseriate, heterocellular. Axial parenchyma apotracheal diffuse or banded. Tyloses common. Sieve tube plastids Ss type, with approx. five globular starch grains. Nodes? Chambered calciumoxalate crystals present in some species.

Trichomes Hairs absent.

LeavesUsually alternate (spiral; rarely opposite), simple, entire, with flat ptyxis. Stipules and leaf sheath absent. Petiole vascular bundles? Venation pinnate. Stomata usually paracytic (sometimes anomocytic or laterocytic). Cuticular wax crystalloids as clustered tubuli (Berberis type), chemically dominated by nonacosan-10-ol. Mesophyll with calciumoxalate druses. Leaf margin usually entire.

Inflorescence Axillary, usually raceme.

Flowers Actinomorphic, small. Hypogyny. Sepals two to six, with imbricate aestivation, very small, or absent. Petals absent. Nectary absent. Disc absent.

Androecium Stamens five to 12 (to 24), usually as many as or twice the number of sepals. Filaments short, free from each other and from tepals. Anthers basifixed, non-versatile, tetrasporangiate, latrorse, longicidal (dehiscing by longitudinal valves); connective often somewhat prolonged. Tapetum secretory. Female and male flowers sometimes with staminodia.

Pollen grains Microsporogenesis simultaneous. Pollen grains usually tricolpate (rarely tricolporoidate), shed as monads, bicellular at dispersal. Exine tectate, with columellate infratectum, microperforate, psilate or verrucate.

Gynoecium Pistil composed of usually two (rarely three or four) connate carpels. Ovary superior, incompletely bilocular (rarely trilocular or quadrilocular). Stylodia usually two (rarely three or four), short, recurved or circinate, connate at base. Stigmas relatively massive, decurrent, with multicellular appendages, non-papillate, Dry type. Male flowers sometimes with pistillodium.

Ovules Placentation apical to axile or parietal. Ovules (one or) two per carpel, anatropous, pendulous, epitropous, bitegmic, crassinucellar. Micropyle exostomal, Z-shaped (zig-zag)? Outer integument three to six cell layers thick. Inner integument four or five cell layers thick. Hypostase present. Megagametophyte monosporous, Polygonum type. Synergids with a filiform apparatus. Endosperm development cellular. Endosperm haustoria? Embryogenesis? Polyembryony sometimes occurring.

Fruit A usually one-seeded (rarely two-seeded) drupe, often with persistent stylodia and staminodia.

Seeds Aril absent. Testa persistent, thin-walled, crushed. Exotegmen? Endotegmen with tannins, and thickened and often sclerotized and cutinized cell walls. Perisperm thin, with protein crystals. Endosperm copious, oily and proteinaceous. Embryo small, straight, apical, well differentiated, chlorophyll? Cotyledons two, as wide as radicula. Germination phanerocotylar.

Cytology n = 16

DNA Mitochondrial intron coxII.i3 lost?

Phytochemistry Flavonols (quercetin, apigenin, luteolin, etc.), Group I carbocyclic iridoids (e.g. asperuloside, daphniphylloside), hydrolyzable tannins, and unique triterpene (squalene) alkaloids of the daphniphylline group (daphniphylline, codaphniphylline etc.) present. Myricetin? Ellagic acid, proanthocyanidins, condensed tannins, and cyanogenic compounds not found. Aluminium accumulated.

Use Ornamental plants.

Systematics Daphniphyllum (c 30; the Western Ghats in southwestern India, Sri Lanka, Missuri to Bhutan in southern Himalayas, southern Tibet, Khasia Hills in Assam, China, the Korean Peninsula and Japan, Taiwan, Southeast Asia, Malesia, New Guinea, the Solomon Islands, tropical Australia, with their largest diversity in Yunnan).

Daphniphyllum is probably sister to Cercidiphyllum (Cercidiphyllaceae).

GROSSULARIACEAE DC.

( Back to Saxifragales )

de Candolle in de Lamarck et A. P. de Candolle, Fl. Franç., ed. 3, 4(2): 405. 17 Sep 1805 [’Grossulariae’], nom. cons.

Grossulariales DC. ex Bercht. et J. Presl, Přir. Rostlin: 236. Jan-Apr 1820 [‘Grossulariae’]; Ribesiaceae Marquis, Esq. Règne Vég.: 66. 15-22 Jul 1820 [’Ribesioïdeae’]

Genera/species 1/c 200

Distribution Temperate parts of Eurasia, the Mediterranean, northeastern Africa, North America to southern Chile.

Fossils Leaves similar to Ribes are known from Eocene and younger sediments in North America.

Habit Usually bisexual (sometimes dioecious), usually deciduous (rarely evergreen) shrubs, upright, creeping (often with subterranean stems) or occasionally somewhat climbing; branches differentiated into long shoots and short shoots. Leaves sometimes modified into spines.

Vegetative anatomy Phellogen ab initio outer-cortical to pericyclic. Subterranean stems with well developed endodermis. Pericyclic fibres absent. Vessel elements usually with scalariform (rarely simple) perforation plates; lateral pits usually alternate (sometimes scalariform), simple or bordered pits. Imperforate tracheary xylem elements fibre tracheids with simple or bordered pits, septate or non-septate (also vasicentric tracheids). Wood rays uniseriate or multiseriate, homocellular or heterocellular. Axial parenchyma usually absent (rarely apotracheal diffuse or paratracheal scanty or banded). Sieve tube plastids Ss type. Nodes 1:1, unilacunar with one leaf trace, or 3:3, trilacunar with three traces. Tanniniferous cells abundant. Non-lignified stem tissues with numerous cystoliths. Calciumoxalate druses present.

Trichomes Hairs unicellular or multicellular, stalked or unstalked, uniseriate or branched, with or without glandular apex, often peltate-lepidote glandular hairs; epidermal prickles frequent at nodes and internodes.

Leaves Alternate (spiral), simple or almost palmately compound, usually lobed (rarely entire), usually with conduplicate-plicate (rarely convolute) ptyxis. Stipules intrapetiolar, membranous, or absent; leaf sheath absent. Petiole vascular bundle transection arcuate?; petiole bundles connate. Venation palmate. Stomata anomocytic (paracytic?). Cuticular waxes? Domatia abaxial, as pockets. Druses present in parenchyma and collenchyma. Tanniniferous cells numerous. Leaf margin usually coarsely serrate; leaf teeth with hydathodes.

Inflorescence Terminal, raceme, usually pendent (sometimes erect).

Flowers Actinomorphic, small. Pedicel articulated. Hypanthium present, with basal nectaries. Epigyny or almost epigyny. Sepals usually five (rarely four), with imbricate or subvalvate aestivation, often petaloid, persistent, usually recurved (sometimes connivent into a tube), free. Petals (in reality staminodia?) usually five (rarely four), with open or imbricate aestivation, scale-like to subulate, persistent, free (rarely absent). Nectariferous disc often quinquelobate.

Androecium Stamens usually five (rarely four), antesepalous, alternipetalous. Filaments filiform, inserted on top of hypanthium, free, adnate to sepals (free from petals?). Anthers usually basifixed (sometimes dorsifixed), non-versatile, tetrasporangiate, introrse, longicidal (dehiscing by longitudinal slits); connective sometimes with apical nectary. Tapetum secretory. Female flowers with staminodia.

Pollen grains Microsporogenesis simultaneous. Pollen grains (5–)8–14-pantoporate or zonocolporate (rarely pentacolpodiorate), shed as monads, bicellular at dispersal. Ectoapertures present (rugulate surfaces surrounding endoapertures). Exine pertectate, with columellate? infratectum, rugulate, punctate or spinulate.

Gynoecium Pistil usually composed of two paracarpous, connate and usually median (sometimes transverse) carpels. Ovary inferior or almost inferior, unilocular. Style single, simple or bifid, or stylodia two, free. Stigmas two, capitate, non-papillate, Wet type. Male flowers with pistillodium.

Ovules Placentation parietal (with two somewhat intruding placentae). Ovules four to more than 100 per ovary, anatropous, bitegmic, crassinucellar. Micropyle exostomal. Outer integument three to five cell layers thick, with tanniniferous outer epidermal cells. Inner integument two or three cell layers thick. Funicular obturator present. Parietal tissue three or four cell layers thick. Hypostase present. Megagametophyte monosporous, Polygonum type. Endosperm development usually cellular (sometimes helobial or nuclear?). Endosperm haustorium chalazal. Embryogenesis irregular.

Fruit A many-seeded berry-like fruit with persistent perianth and staminal remnants.

Seeds Funicular aril surrounding entire or parts of seed. Seed coat endotestal. Exotesta mucilaginous (myxotesta); exotestal cells palisade, large with thin walls; epidermal cells large and pulpy. Endotesta hard; endotestal cells small, cuboid, with calciumoxalate crystals, and with radial and inner walls lignified. Tegmic cells elongate, tanniniferous. Perisperm not developed. Endosperm copious, oily, proteinaceous and with hemicellulose, with somewhat thickened walls. Embryo small, straight, well differentiated, without chlorophyll. Cotyledons two, with main vein ending in hydathodal tooth. Germination phanerocotylar.

Cytology n = 8 (16)

DNA

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), cyanidin, delphinidin, mono- and sesquiterpenes, ellagic acid, ellagitannins, and tyrosine-derived cyanogenic compounds present. Iridoids not found. Aluminium accumulated in some species.

Use Ornamental plants, fruits, tea (leaves from Ribes nigrum), medicinal plants.

Systematics Ribes (c 200; Europe, the Mediterranean, northeastern Africa, temperate Asia, North and Central America, the Pacific coast of South America, the Andes southwards to Tierra del Fuego).

Ribes is sister to Saxifragaceae.

50% majority rule consensus tree of Ribes based on DNA sequence data (Messinger & al. 1999).

HALORAGACEAE R. Br.

( Back to Saxifragales )

Brown in M. Flinders, Voy. Terra Austral. 2: 549. 19 Jul 1814 [’Halorageae’], nom. cons.

Cercodiaceae Juss. in F. Cuvier, Dict. Sci. Nat. 7: 441. 24 Mai 1817 [‘Cercodianae’]; Haloragales Link, Handbuch 2: 52. 4-11 Jul 1829 [’Halorageae’]; Myriophyllaceae Schultz Sch., Nat. Syst. Pflanzenr.: 324. 30 Jan-10 Feb 1832 [’Myriophylleae’]; Haloragineae Engl., Syllabus, ed. 2: 162. Mai 1898 [‘Halorrhagidineae’]

Genera/species 8/c 145

Distribution Largest diversity on the Southern Hemisphere, particularly in Australia; Myriophyllum cosmopolitan; Proserpinaca in North America and the West Indies.

Fossils Obispocaulis myriophylloides and Tarahumara sophiae from the Campanian to the Maastrichtian of Mexico have both been assigned to either Haloragaceae or very close to that clade. Tarahumara had unisexual epigynous flowers with four basally connate uniovulate carpels, and a drupaceous fruit. Obispocaulis is represented by fossil stems containing aerenchyma and bearing adpressed leaves. Cenozoic pollen and fruits of Haloragaceae are frequent in both the Northern and Southern Hemispheres. Fossils of Proserpinaca are known from pre-Pliocene layers in Europe.

Habit Usually monoecious or polygamomonoecious (rarely bisexual or dioecious), perennial or annual herbs, suffrutices or evergreen small shrubs (‘Haloragodendron’ consists of shrubs and small trees). Numerous species are aquatic, other representative are amphibious, hygrophytes or terrestrial mesophytes. Myriophyllum in the Northern Hemisphere produces turions (condensed reproductive and hibernating shoots). The main root in aquatic and amphibious species is replaced by adventitious roots (without root hairs), anchoring the plant to the substrate (adventitious roots in Haloragis inserted between the leaves).

Vegetative anatomy Phellogen? Primary cortex with numerous aerial cavities (especially in aquatic species). Primary vascular tissue strongly reduced in aquatic species. Endodermis significant especially in aquatic species. Secondary lateral growth normal or absent. Vessel elements with simple perforation plates; lateral pits? Imperforate tracheary xylem elements ?, with simple pits (Glischrocaryon). Wood rays uniseriate or multiseriate, homocellular or heterocellular. Axial parenchyma? Sieve tube plastids Ss type. Nodes 1:1, unilacunar with one leaf trace. Calciumoxalate crystals often present in hair-shaped cortical cells.

Trichomes Hairs unicellular or multicellular, uniseriate, often with silica, or absent.

Leaves Usually opposite or verticillate (sometimes alternate, spiral), simple or compound (often pinnately compound), entire or often finely lobed, with conduplicate-flat ptyxis (in Myriophyllum and Proserpinaca heterophylly). Stipules very small or absent; leaf sheath absent. Colleters present? Petiole vascular bundle transection arcuate? Venation pinnate (or leaves one-veined). Stomata usually anomocytic (often absent). Cuticular wax crystalloids usually absent (rarely as parallel grouped platelets, Hypericum type). Leaf margin serrate or entire, eglandular.

Inflorescence Terminal or axillary, thyrso-paniculate, thyrsoid, fasciculate etc., or raceme- or spike-like, or flowers solitary, axillary. Floral prophylls (bracteoles) present or absent.

Flowers Actinomorphic, small. Epigyny. Sepals usually four (in Proserpinaca three, rarely two), with valvate aestivation, persistent (absent in female flowers of Myriophyllum). Petals usually four (in Proserpinaca three, rarely two), with imbricate aestivation, caducous (usually absent in Proserpinaca and female flowers in Myriophyllum and Laurembergia). Nectary absent. Disc absent.

Androecium Stamens usually (two to) four or 4+4, as many as or twice the number of sepals (when four then antesepalous). Filaments short, narrow, free from each other and from tepals. Anthers basifixed, non-versatile, tetrasporangiate, introrse, longicidal (dehiscing by longitudinal slits); connective sometimes slightly prolonged. Tapetum secretory. Antesepalous staminodia present in some species of Gonocarpus.

Pollen grains Microsporogenesis simultaneous. Pollen grains 4–6(–20)-colpate or 4–6(–20)-porate, shed as monads, usually tricellular (rarely bicellular) at dispersal. Exine tectate, with columellate infratectum, microperforate and beset with small supratectal processes.

Gynoecium Pistil composed of usually four (rarely two or three) connate carpels; carpels antepetalous or median carpel adaxial. Ovary inferior, (unilocular to) quadrilocular (septa sometimes poorly developed, absent in Laurembergia and most species of Glischrocaryon). Stylodia separate, clavate, somewhat swollen at base (sometimes absent). Stigmas capitate or penicillate, papillate, Dry type. Pistillodium?

Ovules Placentation apical. Ovules one or two (one aborting) per carpel, anatropous or hemianatropous, pendulous, usually apotropous (sometimes epitropous), bitegmic, crassinucellar (or tenuinucellar?). Micropyle endostomal (Myriophyllum). Outer integument two or three cell layers thick. Inner integument approx. two cell layers thick. Parietal tissue two or three cell layers thick. Archesporial cell hypodermal (Myriophyllum). Funicular obturator poorly developed or absent. Hypostase often present. Nucellar cap often present. Megagametophyte monosporous, Polygonum type. Synergids with a filiform apparatus. Antipodal cells persistent. Endosperm development usually cellular (in Laurembergia and some species of Myriophyllum nuclear). Haustorial suspensor present. Endosperm haustoria? Embryogenesis caryophyllad.

Fruit A one- to four-seeded nut (in Proserpinaca three-seeded), a drupe with one- to four-seeded pyrene (in Meziella) or a schizocarp with two to four nut-like mericarps (in Myriophyllum).

Seeds Aril absent. Seed coat exotestal. Exotesta (sometimes also hypodermal layer) persistent, with thin-walled cells; other parts of testa and tegmen degrading and crushed. Perisperm not developed. Endosperm usually copious, starchy, oily. Embryo usually large, straight, without chlorophyll. Cotyledons two. Germination phanerocotylar.

Cytology n = (6) 7 (8) 14, 28, 42, 56 – Polyploidy occurring.

DNA Mitochondrial intron coxII.i3 lost (Haloragis).

Phytochemistry Flavones, pelargonidin (in leaves), cyanidin, ellagic and gallic acid, tannins, myriophyllin (in hair glands of Myriophyllum), cyanogenic compounds, saponins, and coumaric acid present. Flavonols (kaempferol, quercetin)?

Use Ornamental plants, aquarium plants (Myriophyllum).

Systematics Glischrocaryon (4; southern Western Australia, southern South Australia, New South Wales, Victoria; incl. Haloragodendron?), ‘Haloragodendron’ (5; southwestern Western Australia, southeastern New South Wales, eastern Victoria, Tasmania; paraphyletic; in Glischrocaryon?); Proserpinaca (2–3; southeastern United States, the West Indies), Meionectes (2; southwestern Western Australia, southeastern South Australia, southern Victoria, Tasmania), Trihaloragis (1; T. hexandra; southwestern Western Australia), Haloragis (28; Australia, New Caledonia, New Zealand, Rapa Island, Juan Fernández), Gonocarpus (c 40; Southeast Asia and Malesia to Japan, Australia and New Zealand), Laurembergia (4; tropical and subtropical regions on both hemispheres), Myriophyllum (c 45; cosmopolitan, with their highest diversity in Australia).

Haloragaceae are sister-group to Penthorum (Penthoraceae).

The Haloragodendron clade (probably including Glischrocaryon) is sister to the remaining Haloragaceae. The crown clade is not completely resolved, since Proserpinaca and Meionectes are parts of a basal trichotomy together with the remainder.

Majority rule consensus tree (simplified) from Bayesian analysis of Haloragaceae based on DNA sequence data (Moody & Les 2007).

HAMAMELIDACEAE R. Br.

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Brown in C. Abel, Narr. Journey China: 374. 15 Aug 1818 [‘Hamamelideae’], nom. cons.

Fothergillaceae Nutt., Gen. N. Amer. Pl. 1: 108. 14 Jul 1818 [‘Fothergilleae’]; Fothergillales Link, Handbuch 2: 445. 4-11 Jul 1829 [’Fothergilleae’]; Hamamelidales Link, Handbuch 2: 4. 4-11 Jul 1829 [’Hamamelideae’]; Parrotiaceae Horan., Prim. Lin. Syst. Nat.: 79. 2 Nov 1834 [‘Parrotiaceae (Hamamelideae)’]; Hamamelidopsida Brongn., Enum. Plant. Mus. Paris: xxix, 109. 12 Aug 1843 [’Hamamelineae’]; Bucklandiaceae J. Agardh, Theoria Syst. Plant.: 155. Apr-Sep 1858 [’Bucklandieae’], nom. illeg.; Disanthaceae Nakai, Chosakuronbun Mokuroku [Ord. Fam. Trib. Nov.]: 246. 20 Jul 1943; Rhodoleiaceae Nakai, Chosakuronbun Mokuroku [Ord. Fam. Trib. Nov.]: 246. 20 Jul 1943; Exbucklandiaceae Reveal et Doweld in Novon 9: 552. 30 Dec 1999; Hamamelidineae Thorne et Reveal in Bot. Rev. (Lancaster) 73: 91. 29 Jun 2007

Genera/species 26/95–115

Distribution Eastern and southern Africa, Madagascar, southern Turkey, southeastern Trans-Caucasus, northern Iran, western and eastern Himalaya, Assam, Manipure, East and Southeast Asia to the Korean Peninsula and Japan, Malesia, New Guinea, northeastern Australia (Queensland), eastern North America, Central America, northeastern South America.

Fossils Allonia decandra from the Late Santonian of Georgia (the United States) is a pentamerous male flower with connate sepals and two staminal whorls, tricolpate pollen having reticulate exine and columellate infratectum, and with an adaxial lobate (nectariferous?) disc. Allonia seems to be sister-group to Maingaya. Androdecidua endressii is another pentamerous staminate flower from the Late Santonian of Georgia. Numerous fossils (especially leaves and seeds) of Hamamelidaceae are known from the Cenozoic. Seeds and bilocular fruits of Rhodoleia have been found in Maastrichtian to Miocene layers in Europe.

Habit Usually bisexual (sometimes monoecious, andromonoecious or polygamomonoecious), evergreen or deciduous trees or shrubs.

Vegetative anatomy Phellogen ab initio superficial. Primary vascular tissues as a cylinder, without separate bundles. Vessel elements with usually scalariform (sometimes reticulate) perforation plates; lateral pits usually opposite to scalariform (rarely alternate), simple pits. Vestured pits sometimes present. Imperforate tracheary xylem elements tracheids or fibre tracheids with bordered pits, non-septate. Wood rays uniseriate or multiseriate, homocellular or heterocellular. Axial parenchyma apotracheal diffuse or diffuse-in-aggregates, or paratracheal scanty (or unilateral), or absent. Tyloses sometimes abundant. Sieve tube plastids Ss type, with five (to ten) starch grains. Nodes usually 3:3, trilacunar with three leaf traces (in Chunia and Mytilaria 5:5, pentalacunar with five traces). Medulla in Mytilaria with resiniferous secretory canals. Branched sclereids frequent. Some species possess secretory canals. Parenchyma usually with prismatic calciumoxalate crystals.

Trichomes Hairs usually multicellular (sometimes unicellular), often early sclerified, usually stellate or tufted (sometimes uniseriate).

Leaves Usually alternate (usually distichous, sometimes spiral; rarely opposite), simple, entire, with conduplicate-flat or conduplicate-plicate ptyxis. Stipules usually caducous (sometimes cauline); leaf sheath absent. Petiole vascular bundle transection usually annular (rarely arcuate; petiole sometimes with adaxial bundle). Venation usually palmate or with stout veins at base (rarely pinnate), eucamptodromous or actinodromous and brochidodromous or craspedodromous. Stomata usually paracytic (sometimes laterocytic), often only on adaxial side of lamina. Cuticular wax crystalloids usually absent (rarely as irregular platelets, or as clustered tubuli of Berberis type, chemically dominated by nonacosan-10-ol). Domatia rarely present. Epidermis with or without mucilage cells. Mesophyll with calciumoxalate crystals and usually sclerenchymatous idioblasts with sclereids of different appearance (brachysclereids, columnar, etc.). Leaf margin usually serrate (rarely entire); leaf teeth often fothergilloid (with transparent glandular apex; gland often absent).

Inflorescence Terminal or axillary, thyrse, botryoid, panicle, spike-, catkin- or head-like (rarely raceme; in Rhodoleia pendant capitulate pseudanthium with involucre consisting of bracts).

Flowers Usually actinomorphic. Hypanthium present or absent. Usually epigyny (rarely hypogyny). Sepals (two to) four or five (to seven), usually with imbricate aestivation, usually free (rarely connate), often persistent (rarely absent). Petals (two to) four or five, with open or valvate (or imbricate) aestivation, adaxially circinate, usually band-like, often spirally twisted, sometimes stipitate, caducous, free (rarely absent). Nectaries as an intrastaminal annular nectariferous disc or staminodial nectaries (in Hamamelis), at petal bases (in Disanthus) or as nectariferous glands around filament (in Rhodoleia).

Androecium Stamens (one to) four or five (to 24), in one or two whorls, often as many as sepals, antesepalous. Filaments free from each other and from tepals. Anthers usually basifixed, non-versatile, usually tetrasporangiate (rarely disporangiate), latrorse or introrse, longicidal (usually dehiscing by one or two valves; rarely by longitudinal slits or basal pore); connective usually more or less prolonged. Tapetum secretory, with uni-, bi- or multinucleate cells. Staminodia antepetalous, sometimes alternating with fertile stamens, or absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains usually tricolpate (rarely tetracolpate, pantocolpate, hexarugate,polyrugate or polyforate), shed as monads, bicellular at dispersal. Exine semitectate, with columellate infratectum, reticulate.

Gynoecium Pistil composed of usually two (rarely three) partially or entirely connate carpels. Ovary usually inferior (rarely superior), usually bilocular (rarely trilocular). Stylodia usually two (rarely three), long, free or connate below. Stigmas terminal or decurrent, with multicellular appendages, non-papillate, Dry type. Male flowers often with pistillodium.

Ovules Placentation axile. Ovule usually one or several (rarely numerous) per carpel, anatropous, usually pendulous (along carpellary edges when numerous), apotropous to epitropous (half epitropous, half apotropous), bitegmic, crassinucellar. Micropyle endostomal or bistomal, sometimes Z-shaped (zig-zag). Outer integument usually six to twelve (rarely two) cell layers thick. Inner integument two or three cell layers thick. Hypostase present. Parietal tissue usually eight to ten cell layers thick. Nucellar cap sometimes two cell layers thick. Archespore usually unicellular (rarely multicellular). Megagametophyte monosporous, Polygonum type. Endosperm development usually nuclear (at least in Parrotiopsis cellular). Endosperm haustoria? Embryogenesis chenopodiad (Distylium, Hamamelis) or solanad (Parrotiopsis).

Fruit A loculicidal and/or septicidal double-walled capsule with coriaceous or lignified exocarp and lignified or corneous endocarp, often with persistent calyx (in Rhodoleia a syncarp with capsular unities).

Seeds Aril absent. Hilum large. Seed coat (meso)testal. Testa usually thick, hard, multiplicative, shining and often two-coloured, winged or unwinged. Exotestal cells usually thickened. Mesotesta massive, usually consisting of sclerotized fibrous cells. Tegmen not included in mature seed coat; tegmic cells tanniniferus. Perisperm more or less developed. Endosperm usually sparse, oily. Embryo straight, usually small, well differentiated. Cotyledons two. Germination phanerocotylar. Polyembryony sometimes occurring.

Cytology n = 8, 12 – Polyploidy occurring in some species.

DNA Mitochondrial intron coxII.i3 lost. Plastid gene rpl22 absent.

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), flavone-C-glycosides, cyanidin, delphinidin, ellagic acid, and tannins present. Chalcones, alkaloids, and cyanogenic compounds not found.

Use Ornamental plants, medicinal plants (also healing substances etc. from Hamamelis virginiana), timber.

Systematics Hamamelidaceae are sister-group to the clade [Cercidiphyllaceae+Daphniphyllaceae].

Exbucklandioideae are sister to the remainder.

Exbucklandioideae (A. Reinsch) H. T. Chang in Acta Sci. Nat. Univ. Sunyatseni 1973(1): 54. Nov 1973

3/4–10. Exbucklandia (2; Assam, eastern Himalayas, southern China, the Malay Peninsula, Sumatra), Rhodoleia (1–7; southern China, Southeast Asia to Sumatra), Mytilaria (1; M. laosensis; Guangxi, Laos). – Assam to Southeast Asia and southern China, West Malesia. Inflorescence usually capitate. Epigyny or half epigyny. Petals sometimes absent. Micropyle in Exbucklandia with partially prolonged outer integument. Outer integument in Exbucklandia two cell layers thick. Seed coat in Exbucklandia and Rhodoleia winged. Only exotestal cells thickened. n = 8, 12.

[Disanthoideae+Hamamelidoideae]

Disanthoideae Harms in Engler et Prantl, Nat. Pflanzenfam., ed. 2, 18a: 314. 3 Mai 1930

1/1. Disanthus (1; D. cercidifolius; Japan). – Hypogyny. Nectaries present at petal bases. Anthers dehiscing with longitudinal slits. n = 8.

Hamamelidoideae Burnett, Outlines Bot.: 733, 1132. Feb 1835 [‘Hamamelidae’]

22/90–105. Chunia (1; C. bucklandioides; Hainan), Corylopsis (25–30; Bhutan, China, the Korean Peninsula, Japan), Dicoryphe (12; Madagascar, the Comoro Islands), Distyliopsis (7; Burma, Thailand, Indochina, Taiwan, Malesia), Distylium (10–18; Southeast Asia, Malesia), Embolanthera (2; Southeast Asia, the Philippines), Eustigma (2; southern China, Southeast Asia), Fortunearia (1; F. sinensis; central and eastern China), Fothergilla (2; eastern North America), Hamamelis (4–5; East Asia, eastern North America), Loropetalum (3; northern and northeastern India, Assam, China, Japan), Maingaya (1; M. malayana; Penang and Perak on the Malay Peninsula), Matudaea (2; central Mexico to Honduras), Molinadendron (3; Mexico, Central America), Neostrearia (1; N. fleckeri; northeastern Queensland), Noahdendron (1; N. nicholasii; northeastern Queensland), Ostrearia (1; O. australiana; northeastern Queensland), Parrotia (1; P. persica; southwestern Caspian), Parrotiopsis (1; P. jacquemontiana; Himalayas), Sinowilsonia (1; S. henryi; western and central China), Sycopsis (2–3; Assam, China, Taiwan), Trichocladus (5–6; tropical and southern Africa). – Distribution as for Hamamelidaceae. Leaves with craspedodromous venation. Sepals usually absent (sometimes five to nine). Petals usually absent. Stamens four to 24. Anthers dehiscing by valves. Ovule one (in reality three, two of which sterile) per carpel, usually more or less epitropous (sometimes apotropous). Fruit with ballistic seed dispersal. n = 12. – Corylopsideae Harms in H. G. A. Engler et K. A. E. Prantl, Nat. Pflanzenfam., ed. 2, 18a: 325. 3 Mai 1930 are sister to a clade consisting of Eustigmateae Harms in H. G. A. Engler et K. A. E. Prantl, Nat. Pflanzenfam., ed. 2, 18a: 314. 3 Mai 1930 and Hamamelideae DC., Prodr. 4: 268. late Sep 1830 [‘Hamameleae’] (Li & al. 1999).

Cladogram of Hamamelidaceae based on DNA (nuclear ITS) sequence data (Li & al. 1999).

ITEACEAE J. Agardh

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Agardh, Theoria Syst. Plant.: 151. Apr-Sep 1858, nom. cons.

Iteales Doweld, Tent. Syst. Plant. Vasc.: xxviii. 23 Dec 2001

Genera/species 1/c 20

Distribution Eastern and southern Africa, eastern Himalaya to the Korean Peninsula, Japan, Taiwan, Southeast Asia, West Malesia, southeastern United States.

Fossils Iteaceae fossils – mostly diporate pollen grains, but also leaves, fruits and seeds – have been described from the Eocene to the Pliocene of Europe. Ademanthemum iteoides, a flower fossilized in Baltic amber, may be assigned to Iteaceae. Fossil pollen grains of ’Choristylis’ (Itea) are known from Europe and leaves similar to those in Itea have been found in Eocene and younger layers in western North America.

Habit Bisexual or polygamomonoecious, evergreen or deciduous trees or shrubs (rarely climbing).

Vegetative anatomy Phellogen superficial. Young stem with separate vascular bundles. Medulla septated (by diaphragms?). Vessel elements with scalariform perforation plates; lateral pits opposite to scalariform, bordered pits. Imperforate tracheary xylem elements ? with bordered pits, non-septate. Wood rays uniseriate or multiseriate, heterocellular. Axial parenchyma apotracheal diffuse or diffuse-in-aggregates (sometimes absent). Sieve tube plastids Ss type. Nodes 3:3, trilacunar with three leaf traces. Calciumoxalate druses present in cortex and medulla.

Trichomes Hairs unicellular.

Leaves Alternate (spiral), simple, entire, sometimes coriaceous, with conduplicate ptyxis. Stipules small, subulate, inserted at petiole base or stem, or absent; leaf sheath absent. Petiole vascular bundle transection arcuate? Venation pinnate. Stomata anomocytic (paracytic?). Cuticular wax crystalloids? Leaf margin usually glandular-serrate (rarely entire; in Itea ilicifolia spinose-dentate).

Inflorescence Terminal or axillary, racemose or panicle.

Flowers Actinomorphic, small. Hypanthium present. Hypogyny to epigyny. Sepals five, with open or valvate aestivation, persistent, connate at base into tube. Petals five, with valvate aestivation, persistent, free. Nectariferous disc intrastaminal, annular, on hypanthium rim.

Androecium Stamens five, antesepalous, alternipetalous. Filaments subulate, inserted at margin of nectariferous disc, free from each other and from tepals. Anthers dorsifixed, non-versatile, tetrasporangiate, introrse, longicidal (dehiscing by longitudinal slits); connective slightly prolonged. Tapetum secretory. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains bilateral/heteropolar, usually diporate (rarely triporate), shed as monads, bicellular at dispersal. Exine tectate, with granular infratectum, psilate to scabrate.

Gynoecium Pistil composed of two ab initio free, finally connate carpels. Ovary superior to almost inferior, bilocular. Style single, simple or bifid, at anthesis with connivent stylodia. Stigma capitate or lobate, at anthesis with connivent (often connate) and in fruit separate lobes, non-papillate?, Wet type. Pistillodium absent.

Ovules Placentation axile. Ovules four to c. 50 per carpel, usually bitegmic (in ’Choristylis’ unitegmic), crassinucellar. Micropyle bistomal?, not Z-shaped. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Parietal tissue three (to seven) cell layers thick. Megagametophyte monosporous, Polygonum type. Endosperm development? Endosperm haustoria? Embryogenesis?

Fruit A septicidal capsule with persistent perianth (valves often connate in stigmatic region).

Seeds Aril absent. Seed coat exotestal. Exotestal cells tanniniferous, with thickened outer walls. Mesotesta and endotesta crushed. Tegmen? Perisperm not developed. Endosperm sparse, with lipids and aleuron. Embryo large, curved, well differentiated, chlorophyll? Cotyledons two. Germination?

Cytology n = 11

DNA

Phytochemistry Flavone-C-glycosides, proanthocyanidins (prodelphinidins), tyrosine-derived cyanogenic compounds, and allitol present. Flavonols and ellagic acid not found.

Use Ornamental plants, medicinal plants.

Systematics Itea (c 15; eastern and southern Africa [I. rhamnoides], eastern Himalaya, China, the Korean Peninsula, Japan, Taiwan, Southeast Asia, West Malesia and southeastern United States).

Itea is sister to Pterostemon (Pterostemonaceae).

MEDUSANDRACEAE Brenan

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Brenan in Kew Bull. 7: 228. 25 Jul 1952, nom. cons.

Medusandrales F. Novák ex Takht., Divers. Classif. Fl. Pl.: 353. 24 Apr 1997

Genera/species 1/2

Distribution Central Africa.

Fossils Unknown.

Habit Bisexual, evergreen trees.

Vegetative anatomy Phellogen ab initio superficial. Vessel elements very long, with scalariform perforation plates (with numerous transverse ridges); lateral pits scalariform or opposite, bordered pits. Imperforate tracheary xylem elements fibre tracheids with bordered pits, non-septate? Wood rays usually uniseriate, heterocellular. Axial parenchyma usually paratracheal scanty, or diffuse. Sieve element plastids S type. Nodes? Laticifers present in outer part of medulla, with lemon-coloured latex. Some phloem cells with aggregated crystals.

Trichomes Hairs unicellular, with lignified walls and swollen base.

Leaves Alternate (spiral), simple (unifoliolate?), entire, with ? ptyxis. Stipules cauline, small, early caducous; leaf sheath absent. Petiole apex with pulvinus having complex anatomy. Petiole vascular bundle transection annular; petiole with medullary annular bundle. Venation palmate, with two sides of base converging in apical part of distally swollen petiole (veins arising from base or near base); secondary veins numerous, parallel. Stomata anomocytic. Cuticular wax crystalloids? Leaf margin crenate to weakly serrate.

Inflorescence Axillary, single or pairwise, catkin-like.

Flowers Actinomorphic, small. Hypogyny. Sepals five, with apert, open (valvate?) aestivation, persistent, accrescent, free or connate at base. Petals five, with imbricate aestivation, free. Nectary absent. Disc absent.

Androecium Stamens five, antepetalous. Filaments free, glabrous, free from petals or adnate (epipetalous) at least near base. Anthers dorsifixed, non-versatile, tetrasporangiate, latrorse, valvate (dehiscing by longitudinal recurved valves). Tapetum? Staminodia five, antesepalous, very long (filaments much longer than petals), densely pubescent with clavate hairs, apically with aborted anther reduced to quadrilobate outgrowth.

Pollen grains Microsporogenesis simultaneous? Pollen grains (2–)3-colpor(oid)ate, shed as monads, ?-celled at dispersal. Exine semitectate, infratectum columellate, reticulate.

Gynoecium Pistil composed of usually three (sometimes four) connate carpels. Ovary superior, unilocular, with central column free except at base and apex. Stylodia usually three (sometimes four), separate. Stigma punctate, non-papillate, type? Pistillodium absent.

Ovules Placentation free central-apical. Ovules two per carpel, anatropous, pendulous, epitropous, bitegmic?, crassinucellar? Micropyle ?-stomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Megagametophyte monosporous?, Polygonum type? Endosperm development? Endosperm haustoria? Embryogenesis?

Fruit A single-seeded leathery capsule with persistent, accrescent and strongly recurved sepals.

Seeds Aril absent. Seed coat testal. Testal cells thin-walled. Exotestal cells? Endotesta? Tegmen? Perisperm not developed. Endosperm copious, somewhat ruminate. Embryo minute, straight, chlorophyll? Cotyledons two. Germination?

Cytology n = ?

DNA Insertion of a single base (adenosine) in 18S rDNA (synapomorphy of Saxifragales).

Phytochemistry Unknown. Aluminium accumulation?

Use Unknown.

Systematics Medusandra (2; Cameroon).

Medusandra is sister to Peridiscaceae and assigned to these by Wurdack & Davis (2009). Medusandra and Peridiscaceae share synapomorphies in both morphology and DNA.

PAEONIACEAE Raf.

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Rafinesque, Anal. Nat.: 176. Apr-Jul 1815 [‘Peonidia’], nom. cons.

Paeoniineae Mart., Consp. Regn. Veg.: 40. Sep-Oct 1835 [‘Paeoniaceae’]; Paeoniales Heintze, Cormofyt. Fylog.: 12, 97. 1927; Paeonianae Doweld, Tent. Syst. Plant. Vasc.: xxvii. 23 Dec 2001; Paeoniidae C. Y. Wu in Acta Phytotaxon. Sin. 40: 302. 2002

Genera/species 1/c 25

Distribution South and Southeast Europe, the Mediterranean, subtropical, temperate and subarctic parts of Asia, western North America.

Fossils Uncertain. Paeoniaecarpum hungaricum are fossil fruits from the Miocene of Hungary, which have sometimes been assigned to Paeoniaceae.

Habit Bisexual, perennial herbs, often with root or rhizome tubers, or suffrutices (rarely deciduous shrubs).

Vegetative anatomy Phellogen ab initio inner-cortical. Cortical vascular bundles present. Vessel elements usually with scalariform (sometimes reticulate or simple) perforation plates; lateral pits alternate or transitional (rarely scalariform). Imperforate tracheary xylem elements tracheids with bordered pits, non-septate? Wood rays uniseriate or multiseriate, homocellular or heterocellular (with lignified cell walls). Axial parenchyma apotracheal (some cells among fibres) or paratracheal scanty. Sieve tube plastids Ss type. Nodes 3:3, trilacunar with three leaf traces, or 5:5, pentalacunar with five traces. Calciumoxalate crystals (druses etc.) present.

Trichomes Hairs usually absent (rarely unicellular).

Leaves Alternate (spiral), pinnately compound (sometimes twice or several timespinnately compound) or palmately compound to ternate or simple, lobed, with ? ptyxis. Stipules and leaf sheath absent. Petiole vascular bundle transection annular. Venation palmate. Stomata anomocytic. Cuticular wax crystalloids as transversely ridged rodlets (Aristolochia type), chemically dominated by palmitone (hentriacontan-16-one). Mesophyll with calciumoxalate druses. Leaf margin serrate.

Inflorescence Flowers terminal, usually solitary (sometimes few together in cymose inflorescences). Extrafloral nectaries frequent on bracts enclosing floral buds.

Flowers Actinomorphic, large. Hypogyny. Sepals (three to) five (to seven), with imbricate aestivation, spiral, coriaceous, persistent, free, intergrading into petals. Petals five to eight (to 13), with imbricate aestivation, spiral, caducous, free. Nectariferous disc intrastaminal, annular or lobate, fleshy (developed from receptacle or stamens).

Androecium Stamens c. 50 to more than 150, spiral, initiated from five primordia, centrifugally developing and continuing spiral corolla phyllotaxis. Filaments narrow, more or less connivent in five fascicles (staminal vascular strands five, branched). Anthers basifixed, non-versatile, tetrasporangiate, extrorse, longicidal (dehiscing by longitudinal slits). Tapetum secretory. Staminodia modified into intrastaminal glands or absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolp(oroid)ate, shed as monads, bicellular at dispersal. Exine tectate to semitectate, with columellate infratectum, perforate reticulate, punctate, rugulate, foveolate, or irregularly tuberculate-foveolate.

Gynoecium Carpels (two or) three to eight (to 15), spiral (secondarily), free (secondarily), arcuately diverging. Ovary superior, unilocular (apocarpy). Style very short or absent. Stigma expanded, oblique, papillate, Wet type. Pistillodium absent.

Ovules Placentation marginal (ovules biseriate, inserted on placental outgrowths, and richly vascularized). Ovules approx. ten to more than 100 per carpel, anatropous, bitegmic, crassinucellar (megasporangium degenerating after fertilization or prior to anthesis). Micropyle exostomal to bistomal. Outer integument c. 10 to c. 20 cell layers thick, two-layered. Inner integument three or four cell layers thick. Hypostase present. Parietal tissue approx. five cell layers thick. Nucellar cap massive, approx. twelve cell layers thick. Megasporangium usually absorbed prior to anthesis. Archespore often multicellular (often several germinating). Megagametophyte monosporous, Polygonum type. Synergids with a filiform apparatus. Endosperm development ab initio nuclear. Endosperm haustorium chalazal. Embryogenesis unique among angiosperms, including asymmetrical first division of zygote, degeneration of smaller daughter cell, and free nuclear divisions in larger cell; this resulting in nuclear stage (coenocytic proembryo), from which one or usually several embryos are formed through budding; cell walls produced six or seven (sometimes eight) free nuclear divisions later; only a single embryo maturing.

Fruit An assemblage of sometimes fleshy follicles with persistent calyx.

Seeds Seed large, usually with small fleshy funicular aril. Seed coat mesotestal. Testa a fleshy sarcotesta, vascularized, ab initio red, later black, glossy; in some species developed black fertilized seeds as well as undeveloped showy red unfertilized seeds present. Exotestal cells palisade, thickened. Hypodermis palisade, lignified. Mesotesta sometimes thickened. Endotesta crushed. Tegmen absent. Perisperm not developed. Endosperm copious, oily, with amyloid (xyloglucans). Embryo very small, well differentiated, without chlorophyll. Cotyledons two. Germination phanerocotylar or cryptocotylar.

Cytology n = 5, 10. – Chromosomes 10–15 µm long.

DNA Plastid gene infA defunct (pseudogene present). Mitochondrial intron coxII.i3 lost.

Phytochemistry Flavonols (kaempferol, quercetin etc.), flavones, Group I carbocyclic iridoids, oleanolic acid derivatives, phenolic substances and glycosides (e.g. paeonol, paeonolide, paeonoside, paeoniflorin, oxypaeoniflorin, benzoylpaeoniflorin, and alliflorin), acetophenones, amids and ethereal oils present. Alkaloids? Ellagic acid, proanthocyanidins, tannins, saponins, and cyanogenic compounds not found.

Use Ornamental plants, medicinal plants.

Systematics Paeonia (c 25; southern and southeastern Europe, the Mediterranean, Africa north of Sahara, subtropical, temperate and subarctic Asia, western North America).

Paeonia is sister to the woody Saxifragales clade [Altingiaceae+[Hamamelidaceae+[Cercidiphyllaceae+Daphniphyllaceae]]].

PENTHORACEAE Rydb. ex Britton

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Britton, Man. Fl. N. States: 475. Oct 1901, nom. cons.

Genera/species 1/2

Distribution Northeastern Asia, China, the Korean Peninsula, Japan, northern Vietnam, eastern United States.

Fossils Unknown.

Habit Bisexual, perennial herbs. Helophytes. Roots fibrous.

Vegetative anatomy Phellogen (in root) ab inition superficial. Cortex consisting of outer exodermis and inner aerenchyma. Endodermis? Pericyclic fibres absent. Pseudosiphonostele present in young stems. Secondary lateral growth normal or absent. Vessel elements with scalariform perforation plates; lateral pits?, bordered pits. Imperforate tracheary xylem elements fibre tracheids and tracheids with bordered pits, non-septate (also vasicentric tracheids). Wood rays usually uniseriate or biseriate, homocellular. Axial parenchyma absent. Sieve tube plastids Ss type, with starch, but without protein inclusions. Nodes 1:1, unilacunar with one leaf trace. Crystals?

Trichomes Hairs (in Penthorum sedoides) multicellular, triseriate or quadriseriate, glandular, or absent (in P. chinense).

Leaves Alternate (spiral), simple, entire, with supervolute ptyxis. Stipules and leaf sheath absent. Colleters present. Petiole vascular bundle transection arcuate. Venation pinnate, brochidodromous, with distinct mid-vein. Stomata anomocytic. Cuticular wax crystalloids? Leaf margin glandular serrate; teeth often with apical hydathode.

Inflorescence Terminal or axillary, usually scorpioid monochasium. Bracts lateral, perpendicular to pedicel.

Flowers Actinomorphic. Ab initio epigyny (half epigyny with ovary somewhat sunken into receptacle), later hypogyny. Hypanthium present. Sepals five (to eight), with valvate aestivation, unequal, persistent, connate at base. Petals usually absent (sometimes one to eight, small, free, usually shorter than sepals). Nectary absent. Disc absent.

Androecium Stamens 5+5 (to 8+8), twice as many as sepals. Filaments filiform, free from each other and from tepals. Anthers basifixed, non-versatile, disporangiate, latrorse, longicidal (dehiscing by longitudinal slits). Tapetum secretory. Staminodia five (to eight).

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolporate(or tricolporoidate), shed as monads, ?-cellular at dispersal. Exine tectate, with columellate? infratectum, perforate or microreticulate.

Gynoecium Pistil composed of five (to eight) antesepalous carpels, free or connate at base. Ovary ab initio inferior (semi-inferior) and later superior, unilocular (apocarpy) or multilocular in proximal part. Stylodia five (to eight), short, submarginal. Stigmas small, capitate, type? Pistillodium absent.

Ovules Placentation apical-axile, later intrusive. Ovules numerous per carpel, anatropous, pendulous, bitegmic, crassinucellar. Funicle long. Micropyle ?-stomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Parietal tissue? Megasporangium multicellular in chalazal part only. Megagametophyte monosporous, Polygonum-type. Endosperm development cellular. Basal suspensor cell giving way to micropylar endosperm haustorium. Embryogenesis?

Fruit An assemblage of follicles (with persistent and recurved sepals); free part of carpel circumscissilely dehiscing at base and falling off like a lid.

Seeds Aril absent. Seed coat exotestal. Exotestal cells prominent, papillate, tanniniferous, with thickened outer walls. Other testal cell layers absent. Tegmen crushed, consisting of endostomal micropylar operculum (formed from inner integument). Perisperm not developed. Endosperm sparse. Embryo large, straight; suspensor with strongly enlarged not dividing micropylar cell, chlorophyll? Cotyledons two. Germination? First two pairs of seedling leaves opposite.

Cytology n = 8, 9

DNA

Phytochemistry Mono- and diglycosides of flavonols (kaempferol, quercetin) present. Myricetin, flavones, non-hydrolyzable tannins, and cyanogenic compounds not found.

Use Medicinal plants.

Systematics Penthorum (2; P. chinense: the Russian Far East, China, the Korean Peninsula, Japan, northern Vietnam; P. sedoides: eastern United States from Maine to Ontario and Minnesota, and southwards to Florida and Texas).

Penthorum is sister to Haloragaceae.

PERIDISCACEAE Kuhlm.

( Back to Saxifragales )

Kuhlmann in Arq. Serv. Florest. 3: 4. 1950, nom. cons.

Peridiscales Doweld, New Syllabus Pl. Fam.: 574. Apr 2007

Genera/species 3/11

Distribution Tropical West Africa, tropical South America.

Fossils Unknown.

Habit Bisexual, evergreen trees or shrubs.

Vegetative anatomy Phellogen? Stem cortex with secretory cells and few fibres. Medullary bundles usually absent (present in Peridiscus). Wide primary medullary strands alternating with narrow ones. Vessel elements with scalariform perforation plates; lateral pits scalariform to opposite, bordered pits. Imperforate tracheary xylem elements fibre tracheids and long libriform fibres with bordered pits, usually non-septate. Wood rays uniseriate and homocellular or heterocellular (Soyauxia), or multiseriate heterocellular (Peridiscus, Whittonia). Axial parenchyma apotracheal diffuse. Sieve tube plastids S (Ss?) type. Nodes? Acicular and elongate crystals, crystal sand, styloids, etc. present in parenchyma cells in Soyauxia.

Trichomes Hairs unicellular or absent.

Leaves Alternate (distichous), simple, entire, coriaceous, with ? ptyxis. Stipules single, adaxial, intrapetiolar or pairwise lateral, almost perfoliate, early caducous; leaf sheath absent. Petiole in Peridiscus with pulvinus. Petiole vascular bundle transection annular; petiole with wing bundles (Soyauxia), an adaxial plate (Peridiscus) or adaxial annular bundle (Whittonia). Venation usually pinnate (rarely palmate). Stomata anomocytic or paracytic. Cuticular wax crystalloids as platelets in rosettes. Domatia in vein axils on abaxial side of lamina (Soyauxia?). Idioblasts with crystals. Leaf margin entire.

Inflorescence Axillary, fasciculate, or raceme or spike. Floral prophylls (bracteoles) large, persistent.

Flowers Actinomorphic. Hypogyny to half epigyny. Sepals four to seven, with imbricate aestivation, caducous, free. Petals five with tubular corona (Soyauxia), free, or absent. Nectariferous disc intrastaminal, cupular or annular, sometimes hairy.

Androecium Stamens c. 30 to more than 100; outer much longer than inner. Filaments free or somewhat connate at base into fascicles (Whittonia), free from tepals. Anthers basifixed or subdorsifixed, non-versatile, disporangiate (Peridiscus, Whittonia) or tetrasporangiate (Soyauxia), introrse, longicidal (dehiscing by longitudinal slits, Peridiscus, Whittonia) or by lateral flaps (Soyauxia). Tapetum secretory. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolpor(oid)ate, shed as monads, ?-cellular at dispersal. Exine semitectate (Soyauxia), with columellate infratectum, reticulate (Soyauxia).

Gynoecium Pistil composed of usually three or four (rarely five) carpels, connate in lower parts. Ovary superior to semi-inferior, unilocular (in Soyauxia with central columella). Stylodia three or four, separate, short. Stigmas punctate, non-papillate, type? Pistillodium absent.

Ovules Placentation usually apical (sometimes free central). Ovules usually six to eight per ovary, pendulous, bitegmic?, crassinucellar? Micropyle ?-stomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Megagametophyte monosporous, Polygonum type? Endosperm development nuclear? Endosperm haustoria? Embryogenesis?

Fruit A single-seeded loculicidal capsule (Soyauxia) or a one-seeded drupe (Peridiscus, Whittonia).

Seeds: Aril absent. Seed coat testal. Testal cells tanniniferous (sometimes dark-staining), thin-walled, more or less collapsed. Tegmen? Perisperm not developed. Endosperm copious, cartilagineous, with thick cell walls (or absent?), probably with hemicellulose. Embryo minute, straight? (curved?), well differentiated, chlorophyll? Cotyledons two, foliaceous. Germination?

Cytology n = ?

DNA

Phytochemistry Virtually unknown. Aluminium accumulated.

Use Unknown.

Systematics Soyauxia (7–9; tropical West and Central Africa), Peridiscus (1; P. lucidus; Venezuela, Amazonian Brazil), Whittonia (1; W. guianensis; known only from the type material from below Kaieteur Falls in Guyana and possibly extinct).

The clade [Peridiscaceae+Medusandra] is sister-group to all other Saxifragales.

Soyauxia is probably sister to [Peridiscus+Whittonia]. The position of Whittonia within Peridiscaceae is uncertain due to lack of material, but it is most probably sister to Peridiscus since they share several potential morphological synapomorphies.

PTEROSTEMONACEAE Small

( Back to Saxifragales )

Small in Britton, N. Amer. Fl. 22(1): 2. 22 Mai 1905, nom. cons.

Genera/species 1/3

Distribution Mexico.

Fossils Unknown.

Habit Bisexual, evergreen shrubs.

Vegetative anatomy Phellogen ab initio superficial. Pericyclic fibres weakly developed. Vessel elements (some of them fibre-like) with scalariform or simple perforation plates; lateral pits? Imperforate tracheary xylem elements tracheids (rare), grading into fibre tracheids and libriform fibres. Wood rays uniseriate or multiseriate, heterocellular? Axial parenchyma apotracheal diffuse, or paratracheal scanty. Xylem diffusely porose, non-storied. Sieve tube plastids Ss type. Nodes 3:3, trilacunar with three leaf traces. Secretory cavities absent. Crystals?

Trichomes Hairs unicellular or multicellular, uniseriate, peltate or clavate; glandular hairs cone-shaped to peltate or spherical, multicellular, resin-secreting.

Leaves Alternate (spiral), simple, entire, membranaceous to coriaceous, sticky and resinous on adaxial side, with ? ptyxis. Stipules cauline, very small, early caducous; leaf sheath absent. Petiole vascular bundle transection arcuate? Venation pinnate. Stomata anomocytic. Cuticular waxes? Domatia as pockets in axils of lateral veins on abaxial side of lamina. Secretory cavities absent. Mesophyll with calciumoxalate, usually as druses (usually in association with vascular strands). Leaf margin serrate; leaf teeth with hydathodes.

Inflorescence Terminal or subterminal, few-flowered corymbose cyme.

Flowers Actinomorphic. Hypanthium present. Epigyny. Sepals five, with valvate aestivation, persistent, free. Petals five, with imbricate aestivation, persistent, free. Nectary absent. Disc absent.

Androecium Stamens five, antesepalous, alternipetalous. Filaments flattened, dentate at apex, winged, free from each other and from tepals. Anthers basifixed to dorsifixed, versatile, tetrasporangiate, introrse, poricidal (dehiscing by basal pores). Tapetum secretory. Staminodia five, intrastaminal, antepetalous, as thin filaments without anthers; each staminodium with one lateral tooth.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolporoidate or tricolporate, shed as monads, bicellular or tricellular at dispersal. Exine tectate, with columellate? infratectum, perforate or suprarugulate.

Gynoecium Pistil composed of five connate carpels. Ovary inferior, usually quinquelocular (sometimes sexalocular). Styles five, connate in lower part, short. Stigmas five, quinquelobate, arising more or less radially, type? Pistillodium absent.

Ovules Placentation axile. Ovules four to eight per carpel, anatropous, ascending, apotropous, bitegmic, crassinucellar. Micropyle ?-stomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Parietal tissue approx. seven cell layers thick. Megagametophyte monosporous, Polygonum type? Endosperm development? Endosperm haustoria? Embryogenesis?

Fruit A lignified septicidal usually single-seeded capsule, with persistent upright sepals and recurved petals.

Seeds: Aril absent? Seed coat testal. Testa more or less cartilaginous. Tegmen? Perisperm not developed. Endosperm sparse or absent? Embryo large, well differentiated, chlorophyll? Cotyledons two. Germination?

Cytology n = ?

DNA

Phytochemistry Very insufficiently known. Quercetin-3-O-glycosides and flavone-C-glycosides present. Cyanogenic compounds? Ellagic acid?

Use Unknown.

Systematics Pterostemon (3; high mountains in arid and semiarid regions of central and southern Mexico).

Pterostemon is sister to Itea (Iteaceae).

Pterostemon and Ribes (Grossulariaceae) have similar peltate glandular hairs.

SAXIFRAGACEAE Juss.

( Back to Saxifragales )

de Jussieu, Gen. Plant.: 308. 4 Aug 1789 [’Saxifragae’], nom. cons.

Chrysospleniaceae Bercht. et J. Presl, Přir. Rostlin: 259. Jan-Apr 1820 [’Chrysospleniae’]; Pectiantiaceae Raf., Fl. Tellur. 2: 73. Jan-Mar 1837 [’Pectantidia’]; Saxifragopsida Brongn., Enum. Plant. Mus. Paris: xxviii, 107. 12 Aug 1843 [’Saxifragineae’]; Brachycaulaceae Panigrahi et Dikshit in Panigrahi, Proc. 90th Indian Sci. Congr. Part III (Advance Abstr.): 54. Jan 2003

Genera/species 30–33/650–670

Distribution Mainly in northern temperate and polar areas; a few species in southern temperate regions, and on tropical mountains (in the Andes).

Fossils Uncertain.

Habit Usually bisexual (rarely androdioecious), usually perennial herbs (sometimes annual or biennial, rarely somewhat lignified). Some species are succulent and/or xerophytic.

Vegetative anatomy Phellogen ab initio subepidermal or pericyclic. Cortical and medullary vascular bundles present or absent. Young stem with vascular tissue in separate bundles (pseudosiphonostele). Secondary lateral growth usually absent (sometimes present, normal?). Vessel elements usually with simple (rarely scalariform) perforation plates; lateral pits? Imperforate tracheary elements ? with bordered pits, non-septate?, or absent. Wood rays indistinct. Axial parenchyma? Sieve tube plastids Ss type. Nodes usually 3:3, trilacunar with three leaf traces (sometimes 1:1 [Chrysosplenium], 1:2 [Micranthes], unilacunar with one or two traces, or >3:>3 [Astilbe, etc.], multilacunar with several traces; in some species more than 50 vascular bundles proceeding into petiolar base). Secretory cells with proanthocyanidins and/or ellagitannins. Idioblasts with cyanogenic compounds or druses unusual. Calciumoxalate as druses or acicular crystals present in several genera.

Trichomes Hairs unicellular or multicellular, uniseriate or multiseriate; apex often with multicellular gland; chalk glands present in some species?

Leaves Usually alternate (spiral; usually in basal rosette; rarely opposite in inflorescences), simple or pinnately or palmately compound, entire or lobate, with various types of ptyxis. Often with stipules? in inflorescences; leaves sometimes with persistent stipule-like outgrowths (stipules?) at or near base or on petiole (in Astilbe cauline); leaf base often sheathing. Colleters often present. Petiole vascular bundle transection arcuate or annular; petiole sometimes with medullary or adaxial bundles. Venation palmate or pinnate. Stomata usually anomocytic (sometimes anisocytic or diacytic), often present only on adaxial side of lamina. Cuticular wax crystalloids? Hydathodes frequent. Leaf margin usually serrate, often glandular-serrate (rarely entire).

Inflorescence Terminal, raceme, spike or head, or raceme-, spike- or head-like, or fasciculate or panicle (flowers rarely solitary).

Flowers Usually actinomorphic (rarely obliquely zygomorphic). Hypanthium usually present. Epigyny or half epigyny (sometimes pseudohypogyny; variation also between different morphs of heterostylous species). Sepals (three to) five (to ten), with imbricate or valvate aestivation, median sepal adaxial, free. Petals (four or) five (to ten), with imbricate or valvate aestivation, free (sometimes absent). Nectariferous disc intrastaminal (sometimes absent).

Androecium Stamens (three to) five, alternisepalous (sometimes obhaplostemonous), or (4–)5+(4–)5, obdiplostemonous (rarely up to 15). Filaments free from each other and from tepals. Anthers usually basifixed (rarely somewhat dorsifixed), usually non-versatile, usually tetrasporangiate (in Leptarrhena and Tanakaea disporangiate), introrse or latrorse (in Tolmiea median anthers extrorse and lateral anthers introrse), usually longicidal (dehiscing by longitudinal slits; in Leptarrhena and Tanakaea apically). Tapetum secretory. Staminodia absent?

Pollen grains Microsporogenesis simultaneous. Pollen grains 2–3-colporoidate, 2–3-colpate, 2–3-colporate or 6–9-porate, shed as monads, bicellular at dispersal. Exine tectate or semitectate, with columellate infratectum, perforate, reticulate, or striate, echinulate or spinulate.

Gynoecium Pistil composed of two (to five) usually connate carpels (connate at least at base; in Darmera and certain species of Astilbe free) with various orientation, numerous species with median carpels (some species with oblique carpels), sometimes more or less open ventrally in free distal part. Ovary inferior or semi-inferior, unilocular (apocarpy) or bilocular (rarely trilocular). Stylodia usually two (rarely three), free. Stigmas usually capitate (rarely decurrent), papillate, Dry or Wet type. Pistillodium absent.

Ovules Placentation axile to parietal. Ovules nine to more than 30 per carpel, anatropous, pendulous or ascending, usually bitegmic (in Darmera and Micranthes unitegmic), crassinucellar. Micropyle bistomal, often Z-shaped (zig-zag). Outer integument two cell layers thick. Inner integument two cell layers thick (integument in Darmera four to six cell layers thick). Parietal tissue three to five cell layers thick. Nucellar cap present. Megagametophyte usually monosporous, Polygonum type (rarely disporous, Allium type). Synergids usually with a filiform apparatus. Endosperm development ab initio cellular, helobial or nuclear. Endosperm haustoria of various types present in some species. Embryogenesis solanad.

Fruit Usually a septicidal capsule (sometimes an assemblage of follicles).

Seeds Aril absent? Seed coat exotestal (and sometimes endotegmic), usually with various sculpturing (in Leptarrhena and Sullivantia with wings). Exotestal cells often with outer wall (sometimes radial walls) thickened. Inner pigmented layer often present. Tegmen usually crushed. Endotegmen in Heuchera and Tolmiea thick-walled, crystalliferous. Perisperm not developed. Endosperm usually copious, oily. Embryo usually small (sometimes large), straight, without chlorophyll. Cotyledons two. Germination phanerocotylar.

Cytology x = 7 (most Saxifragaceae), x = 9–14 (many species of Saxifraga), x = 11 (Chrysosplenium, Peltoboykinia), x = 12 (Chrysosplenium), x = 15 (Rodgersia), x = 17 (Astilboides, Bergenia, Darmera, Mukdenia), x = 18 (Rodgersia) – Polyploidy (also autopolyploidy) and aneuploidy often occurring; in Saxifraga the diploid chromosome number varies widely (2n = 12 to c. 220).

DNA Intron absent from plastid gene rpl2. Different combinations of plastid and nuclear genomes present (plastid genome in Tellima also present in Mitella).

Phytochemistry Flavonols (kaempferol, quercetin, myricetin), afzelechin (a flavan-3-ol), cyanidin, oleanolic acid derivatives, bergeniin (C-glycoside of gallic acid), proanthocyanidins (prodelphinidins), hydrolyzable ellagic acid or gallic acid based tannins (tellimagrandin I, tellimagrandin II), condensed tannins (from procyanidin or prodelphinidin), cyanogenic compounds, germacrane-like compounds, and arbutin present. Cyanogenesis via isoleucine or valine. Iridoids not found. Aluminium accumulated in some species.

Use Ornamental plants, medicinal plants.

Systematics Saxifraga (c 390; Europe, arctic and temperate Asia, North Africa, temperate and alpine North America, temperate and alpine South America); Astilbe (c 25; Himalayas, China, Japan, Southeast Asia to New Guinea, eastern North America), Leptarrhena (1; L. pyrolifolia; northwestern North America), Tanakaea (1; T. radicans; China, Japan), Saniculiphyllum (1; S. guangxiense; northwestern Guangxi, southeastern Yunnan), Jepsonia (3; southern California, northwestern Mexico), Telesonix (2; western central North America), Sullivantia (3; the United States), Bolandra (2; western United States), 'Suksdorfia' (3; western North America, Bolivia, Argentina), Boykinia (7; Japan, North America, northwestern Mexico), Cascadia (1; C. nuttallii; Oregon, Washington), Saxifragodes (1; S. albowiana; 51°S in Chile to Tierra del Fuego), Darmera (1; D. peltata; southwestern Oregon, northern California), Astilboides (1; A. tabularis; northern China), Rodgersia (5; Nepal, Himalayas, China, the Korean Peninsula, Japan), Bergenia (6–8; temperate and subtropical regions of western China to Japan), Mukdenia (2; northern China, Manchuria, the Korean Peninsula), Oresitrophe (1; O. rupifraga; northeastern China), Micranthes (68–93; Europe, arctic and temperate Asia, arctic and mountain regions in North America, alpine and mountain regions in Mexico and South America), Peltoboykinia (1; P. tellimoides; Japan), Chrysosplenium (c 60; Europe, temperate and arctic Asia, North America, southern South America), Mitella sensu stricto (North America), Lithophragma (10; western North America), Bensoniella (1; B. oregona; western United States), Tolmiea (2; northwestern North America), 'Heuchera' (c 40; North America, Mexico; polyphyletic), ’Mitella’ (c 20; Siberia, Mongolia, China, the Korean Peninsula, Japan, North America; polyphyletic), Tellima (1; T. grandiflora; western North America), Tiarella (3; East Asia, North America).

Saxifragaceae are sister-group to Ribes (Grossulariaceae).

According to the study by Soltis, Morgan, Grable & al. (1993), Astilbe (Astilbeae Small, Man. S.E. Fl.: 590. 30 Nov 1933), Chrysosplenium (Chrysosplenieae Dumort., Fl. Belg.: 84. 1827) and Peltoboykinia form three basal clades, Astilbe being sister to Saxifragoideae Beilschm. in Flora 16(Beibl. 7): 94. 14 Jun 1833 [‘Saxifrageae’] which comprise all other Saxifragaceae. On the other hand, Deng & al. (2015) reveals Saxifraga as sister to the remaining Saxifragaceae. Two main clades may be identified: the saxifragoids (Saxifrageae Dumort., Fl. Belg.: 84. 1827), the astilboids and the heucheroids (Heuchereae Bartl., Ord. Nat. Plant.: 312. Sep 1830 [‘Heucherea’]).

Cladogram of Saxifragaceae based on DNA restriction site analysis data (Soltis, Morgan, Grable & al. 1993).

Cladogram of Saxifragaceae based on Deng & al. (2015)

TETRACARPAEACEAE Nakai

( Back to Saxifragales )

Nakai, Chosakuronbun Mokuroku [Ord. Fam. Trib. Nov.]: 244. 20 Jul 1943

Genera/species 1/1

Distribution Tasmania.

Fossils Unknown.

Habit Bisexual, evergreen shrub.

Vegetative anatomy Phellogen? Stem without endodermis. Vessel elements with scalariform perforation plates; lateral pits scalariform to opposite. Imperforate tracheary xylem elements very short thick-walled tracheids. Wood rays uniseriate and homocellular, or uniseriate or biseriate and heterocellular. Axial parenchyma apotracheal diffuse or diffuse-in-aggregates, or paratracheal scanty. Sieve tube plastids Ss type. Nodes 1:1, unilacunar with one leaf trace. Crystals?

Trichomes Hairs absent.

Leaves Alternate (spiral), simple, entire, coriaceous, with ? ptyxis. Stipules and leaf sheath absent. Petiole vascular bundle transection arcuate? Venation pinnate. Stomata anomocytic. Cuticular wax crystalloids? Cuticle thick. Leaf margin biserrate; leaf teeth eglandular, possibly with hydathodes (water pores absent).

Inflorescence Terminal, raceme.

Flowers Actinomorphic, small. Hypanthium present? Hypogyny. Sepals four (or five), with imbricate aestivation, persistent, connate at base. Petals four (or five), with imbricate aestivation, stipitate, caducous, free. Nectary absent. Disc absent.

Androecium Stamens four or eight, in one whorl (or two whorls?), antepetalous and alternipetalous. Filaments filiform, connate at base, free from tepals. Anthers basifixed, non-versatile, tetrasporangiate, latrorse, longicidal (dehiscing by longitudinal slits). Tapetum secretory. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolporate, shed as monads, ?-cellular at dispersal. Exine semitectate,with columellate? infratectum, reticulate to rugulate.

Gynoecium Pistil composed of four (or five), stipitate, antepetalous carpels, connate only at base. Ovary superior, unilocular (apocarpy) or usually quadrilocular (sometimes quinquelocular in proximal part?). Stylodia very short. Stigmas small, type? Pistillodium absent.

Ovules Placentation (sub)marginal (ventral, with branched placentae). Ovules c. 15 to more than 100 per carpel, anatropous, bitegmic, crassinucellar. Micropyle exostomal. Outer integument ? cell layers thick. Inner integument ? cell layers thick. Parietal tissue approx. four cell layers thick. Megagametophyte monosporous, Polygonum type. Endosperm development ab initio cellular. Endosperm haustoria? Embryogenesis?

Fruit An assemblage of stalked follicles.

Seeds Aril absent. Seed very small. Seed coat exotestal. Testa thin, with ridges and one or two narrow longitudinal wings, extended at both ends. Exotestal cells longitudinally elongate, with thickened outer walls, without mechanical layers. Inner testal cell layers often crushed. Tegmen? Perisperm not developed. Endosperm copious, fleshy. Embryo very small, chlorophyll? Cotyledons two? Germination?

Cytology n = ?

DNA

Phytochemistry Unknown.

Use Unknown.

Systematics Tetracarpaea (1; T. tasmannica; mountains of Tasmania).

Tetracarpaea is sister to [Haloragaceae+Penthoraceae].


Literature

Abe K. 1982. Embryological studies in the family Saxifragaceae (s.l.) I. Development of the ovule and embryo sac in Saxifraga fortunei var. partita (Makino) Nakai. – Amer. J. Bot. 69: 416-420.

Acevedo-Rosas R, Cameron K, Sosa S, Pell S. 2004. A molecular phylogenetic study of Graptopetalum (Crassulaceae) based on ETS, ITS, rpl16 and trnL-F nucleotide sequences. – Amer. J. Bot. 91: 1099-1104.

Acevedo-Rosas R, Sosa V, Lorea FG. 2004. Phylogenetic relationships and morphological patterns in Graptopetalum (Crassulaceae). – Brittonia 56: 185-194.

Agababian VS. 1960. On the palynosystematics of the family Iteaceae. – Izvest. Akad. Nauk Armajanskoj S.S.R. (Bull. Armenian Acad. Sci., Biol.) 13: 99-102. [In Russian.]

Agababian VS. 1961. Materials toward the palynosystematic study of the family Saxifragaceae s.l. – Izvest. Biol. Nauki 14: 45-61. [In Russian]

Agababian VS. 1963. Pollen morphology of the genus Ribes. – Izvest. Akad. Nauk Armajanskoj S.S.R. 16: 93-98.

Agababian VS. 1964. Evolution of pollen in the order Cunoniales and Saxifragales in relation to some questions of their systematics and phylogeny. – Izvest. Akad. Nauk Armajanskoj S.S.R. 17: 59-72.

Aiken SG. 1979. North American species of Myriophyllum (Haloragaceae). – Ph.D. diss., University of Minnesota, Minneapolis, Minnesota.

Akiyama S, Ohba H, Wu S-K. 2001. A new variety of Sinocrassula paoshingensis (S. H. Fu) H. Ohba et al. (Crassulaceae). – J. Jap. Bot. 76: 222-226.

Alexander EJ. 1942. A new Mexican Sedum. – Cact. Succ. J. 14: 76-78.

Alm T. 2004. Ethnobotany of Rhodiola rosea (Crassulaceae) in Norway. – Sida 21: 321-344.

Al-Shammary KI. 1991. Systematic studies of the Saxifragaceae, chiefly from the Southern Hemisphere. – Ph.D. diss., University of Leicester, England.

Al-Shammary KI, Gornall RJ. 1994. Trichome anatomy of the Saxifragaceae s.l. from the Southern Hemisphere. – Bot. J. Linn. Soc. 114: 99-131.

Babalola KA, Victoria AA. 2009. Foliar epidermal morphology of two West African genera of Haloragaceae R. Br. (Saxifragales). – J. Sci. Res. Dev. 11: 84-91.

Baehni C. 1937. Villadia et Altamiranoa. Étude sur la fusion de deux genres de Crassulacées. – Candollea 7: 283-286.

Bahadur B, Ramaswamy N, Srikanth R. 1986. Studies on the floral biology and nectar secretion in some Kalanchoe species (Crassulaceae). – In: Kapil RP (ed), Pollination biology – an analysis, Inter-India Publ., New Delhi, pp. 251-259.

Baldwin JT Jr. 1935. Somatic chromosome numbers in the genus Sedum. – Bot. Gaz. 96: 558-564.

Baldwin JT Jr. 1937. The cyto-taxonomy of the Telephium sections of Sedum. – Amer. J. Bot. 24: 126-132.

Baldwin JT Jr. 1938. Kalanchoe: the genus and its chromosomes. – Amer. J. Bot. 25: 572-579.

Baldwin JT Jr. 1939. Certain cytophyletic relations in the Crassulaceae. – Chronica Bot. 5: 415-417.

Baldwin JT Jr. 1940. Cytophyletic analysis of certain annual and biennial Crassulaceae. – Madroño 5: 184-192.

Baldwin JT Jr, Speese BM. 1951. Penthorum: its chromosomes. – Rhodora 53: 89-91.

Bañares Baudet Á. 1990. Híbridos de la familia Crassulaceae en las Islas Canarias. Novedades y datos corológicos II. – Vieraea 18: 65-85.

Bañares Baudet Á. 1992. Aeonium pseudourbicum sp. nov. (Crassulaceae), nuevo endemismo de Tenerife (Islas Canarias). – An. Jard. Bot. Madrid 50: 175-182.

Bañares Baudet Á. 1999. Notes on the taxonomy of Aeonium urbicum and A. appendiculatum sp. nov. (Crassulaceae). – Willdenowia 29: 95-103.

Bañares Baudet Á. 2002. On some poorly known taxa of Aichryson sect. Aichryson and A. bituminosum sp. nov. (Crassulaceae). – Willdenowia 32: 221-230.

Bañares Baudet Á, Scholz S. 1990. Monanthes wildpretii sp. nov. (Crassulaceae), nuevo endemismo de Tenerife (Islas Canarias). – Stud. Bot. 9: 129-138.

Bañares Baudet Á, Gómez MVM, Scholz S. 2008. Taxonomic and nomenclatural notes on Crassulaceae of the Canary Islands, Spain. – Willdenowia 38: 475-489.

Barabé D. 1984. Application du cladisme à la systématique des angiosperms: cas des Hamamélidales. – Candollea 39: 51-70.

Barber HN. 1941. Evoluton in genus Paeonia. – Nature 148(3747): 227-228.

Baskin JM, Baskin CC. 1972. Germination characteristics of Diamorpha cymosa seeds and an ecological interpretation. – Oecologia 10: 17-28.

Baskin JM, Baskin CC. 1977. Germination ecology of Sedum pulchellum Michx. (Crassulaceae). – Amer. J. Bot. 64: 1242-1247.

Bates JC. 1933. Comparative anatomical research within the genus Ribes. – Univ. Kansas Sci. Bull. 21: 369-398.

Bate-Smith EC. 1976. Chemistry and taxonomy of Ribes. – Biochem. Syst. Ecol. 4: 13-23.

Bawa SB. 1969a. Embryological studies on the Haloragidaceae II. Laurembergia brevipes Schindl. and a discussion of systematic considerations. – Proc. Natl. Inst. Sci. India, Sect. B, 35: 273-290.

Bawa SB. 1969b. Embryological studies on the Haloragidaceae III. Myriophyllum intermedium DC. – Beitr. Biol. Pflanzen 45: 447-464.

Bawa SB. 1970. Haloragaceae. – Bull. Natl. Sci. Acad. India 41: 226-229.

Bayer C. 2006. Peridiscaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 297-300.

Beamish KI, Lin SC. 1965. Fertilization and seed development in Saxifraga integrifolia Hook. – Can. J. Bot. 43: 861-865.

Behnke H-D. 1986. Contributions to the knowledge of sieve-element plastids in Gunneraceae and allied families. – Plant Syst. Evol. 151: 215-222.

Benedict JC, Pigg KB, DeVore ML. 2008. Hamawilsonia boglei gen. et sp. nov. (Hamamelidaceae) from the Late Paleocene Almont flora of central North Dakota. – Intern. J. Plant Sci. 169: 687-700.

Bensel CR, Palser BF. 1975. Floral anatomy in the Saxifragaceae sensu lato II. Saxifragoideae and Iteoideae. – Amer. J. Bot. 62: 661-675.

Berbeek-Reuvers AAML. 1980. Grossulariaceae. – In: Punt W, Clarke GCS (eds), The Northwest European pollen flora, Elsevier, New York, pp. 107-116.

Berger A. 1924. A taxonomic review of currants and gooseberries. – New York Agric. Exp. Sta. Techn. Bull. 109: 3-118.

Berger A. 1930. Crassulaceae. – In: Engler A, Harms H (eds), Die natürlichen Pflanzenfamilien, 2. Aufl., Bd. 18a, W. Engelmann, Leipzig, pp. 352-483.

Bhatnagar AK, Garg M. 1977. Affinities of Daphniphyllum – palynological approach. – Phytomorphology 27: 92-97.

Bhatnagar AK, Kapil RN. 1982. Seed development in Daphniphyllum himalayense with a discussion on taxonomic position of Daphniphyllaceae. – Phytomorphology 32: 66-81.

Bhatnagar AK, Garg M. 1977. Affinities of Daphniphyllum – palynological approach. – Phytomorphology 27: 92-97.

Bogle AL. 1968. Floral vascular anatomy and the nature of the hamamelidaceous flowers. – Ph.D. diss., University of Minnesota, Minneapolis, Minnesota.

Bogle AL. 1970. Floral morphology and vascular anatomy of the Hamamelidaceae: the apetalous genera of Hamamelidoideae. – J. Arnold Arbor. 51: 310-366.

Bogle AL. 1984. Floral morphology and vascular anatomy of Maingaya Oliv. (Hamamelidaceae, Hamamelidoideae, Hamamelideae). – Amer. J. Bot. 71: 19.

Bogle AL. 1986. The floral morphology and vascular structure of the Hamamelidaceae subfamily Liquidambaroideae. – Ann. Missouri Bot. Gard. 73: 325-347.

Bogle AL. 1987. Inflorescence and flower ontogeny in the pseudanthium of Rhodoleia (Hamamelidaceae). – Amer. J. Bot. 74: 607-608.

Bogle AL. 1989. The floral morphology, vascular anatomy, and ontogeny of the Rhodoleioideae (Hamamelidaceae) and their significance in relation to the ’lower’ hamamelids. – In: Crane PR, Blackmore S (eds), Evolution, systematics, and fossil history of the Hamamelidae 1: Introduction and ‘lower’ Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 201-226

Bogle AL. 1990. Multilacunar nodal anatomy in Mytilaria (Hamamelidaceae). – J. Arnold Arbor. 71: 111-118.

Bogle AL, Philbrick CT. 1980. A generic atlas of hamamelidaceous pollens. – Contr. Gray Herb. 210: 29-103.

Bohm BA. 1979. Flavonoids of Tolmiea menziesii. – Phytochemistry 18: 1079-1080.

Bohm BA. 1993. External and vacuolar flavonoids of Ribes viscosissimum. – Biochem. Syst. Evol. 21: 745.

Bohm BA, Bhat UG. 1985. Flavonoids of Astilbe and Rodgersia compared to Aruncus. – Biochem. Syst. Ecol. 13: 437-440.

Bohm BA, Collins FW. 1979. Flavonoids of some species of Chrysosplenium. – Biochem. Syst. Ecol. 7: 195-201.

Bohm BA, Ornduff R. 1978. Chemotaxonomic studies in the Saxifragaceae s.l. 9. Flavonoids of Jepsonia. – Madroño 52: 39-43.

Bohm BA, Wilkins CK. 1976. Flavonoids and gallic acid derivatives from Peltiphyllum peltatum. – Phytochemistry 15: 2012-2013.

Bohm BA, Wilkins CK. 1978a. The flavonoids of Heuchera cylindrica. – Can. J. Bot. 56: 1174-1176.

Bohm BA, Wilkins CK. 1978b. Chemosystematic studies in the Saxifragaceae s.l. 8. The flavonoids of Elmera racemosa (Watson) Rydberg. – Brittonia 30: 327-333.

Bohm BA, Collins FW, Bose R. 1977a. Flavonoids of Bergenia, Francoa, and Parnassia. – Biochem. Syst. Ecol. 13: 221-233.

Bohm BA, Collins FW, Bose R. 1977b. Flavonoids of Chrysosplenium tetrandrum. – Phytochemistry 16: 1205-1209.

Bohm BA, Donevan LS, Bhat UG. 1986. Flavonoids of some species of Bergenia, Francoa, Parnassia and Lepuropetalon. – Biochem. Syst. Ecol. 14: 75-77.

Bohm BA, Chalmers G, Bhat UG. 1988. Flavonoids and the relationship of Itea to the Saxifragaceae. – Phytochemistry 27: 2651-2653.

Bohm BA, Yang JY, Page JE, Soltis DS. 1999. Flavonoids, DNA and relationships of Itea and Pterostemon. – Biochem. Syst. Ecol. 27: 79-83.

Boiteau P, Allorge-Boiteau L. 1995. Kalanchoe (Crassulacées) de Madagascar. Systématique, écophysiologie et phytochimie. – Karthala, Paris.

Borissova AG. 1969. Konspekt sistemy sem. Crassulaceae DC. flory SSSR (dobavlenija is ismenenija). – Novosti Sist. Vyšs. Rast. 6: 112-121.

Böttcher W, Jäger EJ. 1984. Zur Interpretation der Verbreitung der Gattung Sedum L. s.l. (Crassulaceae) und ihrer Wuchsformtypen. – Wissensch. Zeitschr. Univ. Halle 33: 127-141.

Boutique R, Verdcourt B. 1973. Haloragaceae. – In: Milne-Redhead E, Polhill RM (eds), Flora of tropical East Africa, Balkema, London, Rotterdam, pp. 1-4.

Bowman RN. 1983. Intraspecific variability of leaf cuticle alkanes in Sedum lanceolatum along an elevational gradient. – Biochem. Syst. Ecol. 11: 195-198.

Bramwell D. 1968. Notes on the taxonomy and nomenclature of the genus Aichryson. – Bol. Inst. Nac. Invest. Agron. (Madrid) 28: 203-213.

Bramwell D. 1970. Generic delimitation of the Sempervivum group. – Natl. Cact. Succ. J. 25: 50-51.

Brenan JPM. 1952. Plants of the Cambridge Expedition, 1947-1948: II. A new order of flowering plants from the British Cameroons. – Kew Bull. 7: 227-236.

Brenan JPM. 1954. Soyauxia, a new genus of Medusandraceae. – Kew Bull. 9: 507-511.

Brennan RM. 1992. Currants and gooseberries (Ribes). – In: Moore JN, Ballington JR (eds), Genetic resources of temperate fruit and nut crops, International Society of Horticultural Sciences, Wageningen, pp. 457-488.

Breuer B, Stuhlfauth T, Fock H, Huber H. 1987. Fatty acids of some Cornaceae, Hydrangeaceae, Aquifoliaceae, Hamamelidaceae and Styracaceae. – Phytochemistry 26: 1441-1445.

Britton EG. 1887. Elongation of the inflorescence of Liquidambar. – Bull. Torrey Bot. Club 14: 95-96.

Britton NL, Rose JN. 1903. New or noteworthy North American Crassulaceae. – Bull. New York Bot. Gard. 3: 1-45.

Britton NL, Rose JN. 1904. Lenophyllum, a new genus of Crassulaceae. – Smithsonian Misc. Coll. 47: 159-162.

Britton NL, Rose JN. 1909. Thompsonella, a new genus of Crassulaceae from Mexico. – Contr. U.S. Natl. Herb. 12: 391-392.

Brochmann C, Xiang Q-Y, Brunsfeld SJ, Soltis DE, Soltis PS. 1998. Molecular evidence for polyploid origins in Saxifraga (Saxifragaceae): the narrow arctic endemic S. svalbardensis and its widespread allies. – Amer. J. Bot. 85: 135-143.

Brown RW. 1939. Fossil leaves, fruits, and seeds of Cercidiphyllum. – J. Palaeontol. 13: 485-499.

Byalt VV. 1997. Meterostachys sikokianus (Crassulaceae), a new species and genus for the flora of China. – Bot. Žurn. 82: 128-130. [In Russian with English summary]

Byalt VV. 1998. Orostachys paradoxa, a rare species from the Russian Far East. – Cact. Succ. J. 70: 262-263.

Byalt VV, Sokolova IV. 1999. Ohbaea Byalt & I. V. Sokolova, a replacement name for Balfouria (H. Ohba) H. Ohba (Crassulaceae). – Kew Bull. 54: 476.

Bywater M. 1980. Observations on seeds of Crassula sect. Rosulares. – Kew Bull. 35: 401-402.

Bywater M, Wickens GE. 1983. New World species of the genus Crassula. – Kew Bull. 39: 699-728.

Caballero A, Jiménez MS. 1977. Contribución al estudio anatómico foliar de las crassuláceas canarias. – Vieraea 7: 115-132.

Calder JA, Savile DBO. 1960. Studies in Saxifragaceae III. Saxifraga odontolma and lyalli and North American subspecies of S. punctata. – Can. J. Bot. 38: 409-435.

Calie PJ. 1981. Systematic studies in Sedum section Ternata (Crassulaceae). – Brittonia 33: 498-507.

Camp WH, Hubbard MM. 1963. Vascular supply and structure of the ovule and aril in peony and of the aril in nutmeg. – Amer. J. Bot. 50: 174-178.

Carlquist SJ. 1982. Wood anatomy of Daphniphyllaceae: ecological and phylogenetic considerations, review of pittosporalean families. – Brittonia 34: 252-266.

Carlström A. 1985. Two new species of Sedum (Crassulaceae) from S Greece and SW Turkey. – Willdenowia 15: 107-113.

Carlsward BS, Judd WS, Soltis DE, Manchester S, Soltis PS. 2011. Putative morphological synapomorphies of Saxifragales and their major subclades. – J. Bot. Res. Inst. Texas 5: 179-196.

Carniel K. 1967. Über die Embryobildung in der Gattung Paeonia. – Österr. Bot. Zeitschr. 114: 4-19.

Carrillo-Reyes P, Lomelí-Sención JA. 2008. Sedum chazaroi (Crassulaceae), an endemic new species from southern Jalisco, Mexico. – Bol. Soc. Bot. Mexico 83: 77-80.

Carrillo-Reyes P, Sosa V, Mort ME. 2008. Thompsonella and the “Echeveria group“ (Crassulaceae): phylogenetic relationships based on molecular and morphological characters. – Taxon 57: 863-874.

Carrillo-Reyes P, Sosa V, Mort ME. 2009. Molecular phylogeny of the Acre clade (Crassulaceae): dealing with the lack of definitions for Echeveria and Sedum. – Mol. Phylogen. Evol. 53: 267-276.

Castroviejo S, Calvo R. 1981. Datos citotaxonomicos en Sedum series Rupestria Berger. – Anal. Jard. Bot. Madrid 38: 37-50.

Catling PM, Dumouchel L, Brownell VR. 1998. Pollination of the Miccosukee Gooseberry (Ribes echinellum). – Castanea 63: 402-407.

Cave MS, Arnott HJ, Cook SA. 1961. Embryogeny in the California paeonies with reference to their taxonomic position. – Amer. J. Bot. 48: 397-404.

Ceska O. 1977. Studies in aquatic macrophytes XVII: phytochemical differentiation of Myriophyllum taxa collected in British Columbia. – Water Investigation Branch, Ministry of Environment Victoria, British Columbia.

Chang CT. 1959. The pollen morphology of Liquidambar L. and Altingia Nor. – Bot. Žurn. 44: 1375-1380. [In Russian with English summary]

Chang H-T. 1948. Additions to the hamamelidaceous flora of China. – Sunyatsenia 7: 63-74.

Chang H-T. 1962. Semiliquidambar, novum Hamamelidacearum genus Sinicum. – Sunyatsen Univ. Bull. Nat. Sci. 1: 34-44. [In Chinese]

Chang H-T. 1973. A revision of the hamamelidaceous flora of China. – Sunyatsen Univ. Bull. Nat. Sci. 1: 54-71. [In Chinese]

Chapman M. 1933. The ovule and embryo sac of Saxifraga virginiensis. – Amer. J. Bot. 20: 151-158.

Clausen RT. 1940. Studies in the Crassulaceae: Villadia, Altamiranoa, and Thompsonella. – Bull. Torrey Bot. Club 67: 195-198.

Clausen RT. 1943. The section Sedastrum of Sedum. – Bull. Torrey Bot. Club 70: 289-296.

Clausen RT. 1959. Sedum of the Trans-Mexican Volcanic Belt: an exposition of taxonomic methods. – Cornell University Press, Ithaca, New York.

Clausen RT. 1975. Sedum of North America North of the Mexican Plateau. – Cornell University Press, Ithaca, New York.

Clausen RT. 1977. Biennial species of Sedum of the Sierra Madre Occidental and the Mexican Plateau. – Bull. Torrey Bot. Club 104: 209-217.

Clausen RT. 1979. Sedum in six areas of the Mexican Cordilleran Plateau. – Bull. Torrey Bot. Club 106: 205-216.

Collins FW, Bohm BA. 1974. Chemotaxonomic studies in the Saxifragaceae s.l. 1. The flavonoids of Tellima grandiflora 52: 307-312.

Collins FW, Bohm BA, Wilkins CK. 1975. Flavonol glycoside gallates from Tellima grandiflora. – Phytochemistry 14: 1099-1102.

Conradi R. 1960. Astilbe. – Norsk Hagetid. 76: 192-193.

Conti E, Soltis DE, Hardig TM, Schneider J. 1999. Phylogenetic relationships of the silver saxifrages (Saxifraga, sect. Ligulatae Haworth): implications for the evolution of substrate specificity, life histories, and biogeography. – Mol. Phylogen. Evol. 13: 536-555.

Crane PR. 1984. A reevaluation of Cercidiphyllum-like plant fossils from the British early Tertiary. – Bot. J. Linn. Soc. 89: 199-230.

Crane PR, Stockey RA. 1985. Growth and reproductive biology of Joffrea speirsii gen. et sp. nov., a Cercidiphyllum-like plant from the Late Paleocene of Alberta, Canada. – Can. J. Bot. 63: 340-364.

Crane PR, Stockey RA. 1986. Morphology and development of pistillate inflorescences in extant and fossil Cercidiphyllaceae. – Ann. Missouri Bot. Gard. 73: 382-393.

Crepet WL, Nixon KC, Friis EM, Freudenstein JV. 1992. Oldest fossil flowers of hamamelidaceous affinity, from the Late Cretaceous of New Jersey. – Proc. Natl. Acad. Sci. U.S.A. 89: 8986-8989.

Croizat L. 1941. On the systematic position of Daphniphyllum and its allies. – Lingnan Sci. J. 20: 79-103.

Dahlgren KVO. 1930. Zur Embryologie der Saxifragoideen. – Svensk Bot. Tidskr. 24: 429-448.

Dandy JE. 1927. The genera of Saxifragaceae. – In: Hutchinson J (ed), Contributions towards a phylogenetic classification of flowering plants, Kew Bull. 6: 100-118.

Dark SOS. 1936. Meiosis in diploid and tetraploid Paeonia species. – J. Genet. 32: 353-372.

Darlington CD. 1929. A comparative study of the chromosome complement in Ribes. – Genetica 11: 267-272.

Davezac T. 1957. La place systématique du genre Paeonia et forme de jeunesse de P. lusitanica Mill. – Bull. Soc. Hist. Natur. Toulouse 92: 197-201.

Davis CC, Chase MW. 2004. Elatinaceae are sister to Malpighiaceae; Peridiscaceae belong to Saxifragales. – Amer. J. Bot. 91: 262-273.

Deng J-B, Drew BT, Mavrodiev EV, Gitzendanner MA, Soltis PS, Soltis DE. 2015. Phylogeny, divergence times, and historical biogeography of the angiosperm family Saxifragaceae.– Molec. Phylogen. Evol. 83: 86-98.

Denton MF. 1979. Cytological and reproductive differentiation in Sedum section Gormania (Crassulaceae). – Brittonia 31: 197-211.

Denton MF. 1982. Revision of Sedum section Gormania (Crassulaceae). – Brittonia 34: 48-77.

Denton MF, Kerwin JL. 1980. Survey of vegetative flavonoids of Sedum section Gormania (Crassulaceae). – Can. J. Bot. 58: 902-905.

Deschatres R. 1954. Recherches sur la phyllotaxie du genre Sedum. – Rev. Gén. Bot. 61: 501-570.

Descoings B. 2006. Le genre Kalanchoe (Crassulaceae): structure et définition. – J. Bot. Soc. France 33: 3-28.

Dickison WC. 1975. Studies on the floral anatomy of the Cunoniaceae. – Amer. J. Bot. 62: 433-447.

Dickison WC. 1980a. Diverse nodal anatomy of the Cunoniaceae. – Amer. J. Bot. 67: 975-981.

Dickison WC. 1980b. Comparative wood anatomy and evolution of the Cunoniaceae. – Allertonia 2: 281-321.

Dickison WC, Hils HM, Lugansky TW, Stern WL. 1994. Comparative anatomy and systematics of woody Saxifragaceae. Aphanopetalum Endl. – Bot. J. Linn. Soc. 114: 167-182.

Dong W, Xu C, Cheng T, Lin K, Zhou S. 2013. Sequencing angiosperm plastid genomes made easy: a complete set of universal primers and a case study on the phylogeny of Saxifragales.– Genome Biol. Evol. 2013: 5: 989-997.

Donoghue MJ, Doyle JA. 1989. Phylogenetic analysis of angiosperms and the relationships of the Hamamelidae. – In: Crane PR, Blackmore S (eds), Evolution, systematics, and fossil history of the Hamamelidae 1: Introduction and ”lower” Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 17-45.

Dorofeev PI. 1976. K sistematike neogenovych Proserpinaca Belorusii. – Doklady Akademia Nauk SSSR 20: 1036-1038.

Ebel F, Hagen A, Kümmel F. 1991a. Beobachtungen zur Wuchsrhythmik von Orostachys spinosus (L.) Sweet (Crassulaceae). – Wissensch. Zeitschr. Univ. Halle 40: 47-68.

Ebel F, Hagen A, Kümmel F. 1991b. Beobachtungen zur Wuchsrhythmik und “Knospenbildung” einiger Greenovia- und Aeonium-Arten (Crassulaceae). – Flora 85: 187-200.

Egger K, Reznik H. 1961. Die Flavonolglykoside der Hamamelidaceen. – Planta 57: 239-249.

Eggli U. 1988. A monographic study of the genus Rosularia (Crassulaceae). – Bradleya [Suppl.] 6: 1-119.

Eggli U (ed). 2003. Illustrated handbook of succulent plants VI. Crassulaceae. – Springer, Berlin.

Eggli U, ‘t Hart H, Nyffeler R. 1995. Towards a consensus classification of the Crassulaceae. – In: ‘t Hart H, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys Publ. Leiden, pp. 173-192.

Elst P van der. 1909. Beiträge zur Kenntnis der Samenauflage der Saxifragaceae. – Ph.D. diss., University of Utrecht, The Netherlands.

Elvander PE. 1984. The taxonomy of Saxifraga (Saxifragaceae) section Boraphila subsection Integrifoliae in western North America. – Syst. Bot. Monogr. 3: 1-44.

Endress PK. 1967. Systematische Studie über die verwandtschaftlichen Beziehungen zwischen den Hamamelidaceen und Betulaceen. – Bot. Jahrb. Syst. 87: 431-525.

Endress PK. 1968. Zur systematischen Stellung von Parrotia C. A. Mey. und Sycopsis Oliv. und zum neuen Bastard xSycoparrotia semidecidua P. Endress et J. Anliker. – Schweiz. Beitr. Dendrol. 16-18: 11-28.

Endress PK. 1969. Molinadendron, eine neue Hamamelidaceen-Gattung aus Zentralamerika. – Bot. Jahrb. Syst. 89: 354-359.

Endress PK. 1970. Die Infloreszenzen der apetalen Hamamelidaceen, ihre grundsätzliche morphologische und systematische Bedeutung. – Bot. Jahrb. Syst. 90: 1-54.

Endress PK. 1971. Blütenstände und morphologische Interpretation der Blüten bei apetalen Hamamelidaceen. – Ber. Deutsch. Bot. Ges. 84: 183-185.

Endress PK. 1976. Die Androeciumanlage bei polyandrischen Hamamelidaceen und ihre systematische Bedeutung. – Bot. Jahrb. Syst. 97: 436-457.

Endress PK. 1977. Evolutionary trends in the Hamamelidales-Fagales group. – In: Kubitzki K (ed), Flowering plants: evolution and classification of higher categories, Plant Syst. Evol. [Suppl.] 1: 321-347.

Endress PK. 1978a. Stipules in Rhodoleia (Hamamelidaceae). – Plant Syst. Evol. 130: 157-160.

Endress PK. 1978b. Blütenontogenese, Blütenabgrenzung und systematische Stellung der perianthlosen Hamamelidoideae. – Bot. Jahrb. Syst. 100: 249-317.

Endress PK. 1989a. Aspects of evolutionary differentiation of the Hamamelidaceae and the Lower Hamamelididae. – Plant Syst. Evol. 162: 193-211.

Endress PK. 1989b. A suprageneric taxonomic classification of the Hamamelidaceae. – Taxon 38: 371-376.

Endress PK. 1989c. Phylogenetic relationships in the Hamamelidoideae. – In: Crane PR, Blackmore S (eds), Evolution, systematics, and fossil history of the Hamamelidae 1: Introduction and ‘lower’ Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 227-240.

Endress PK. 1993a. Cercidiphyllaceae. – In: Kubitzki K, Rohwer JG, Bittrich V (eds), The families and genera of vascular plants II. Flowering plants. Dicotyledons. Magnoliid, hamamelid and caryophyllid families, Springer, Berlin, Heidelberg, New York, pp. 250-252.

Endress PK. 1993b. Hamamelidaceae. – In: Kubitzki K, Rohwer JG, Bittrich V (eds), The families and genera of vascular plants II. Flowering plants. Dicotyledons. Magnoliid, hamamelid and caryophyllid families, Springer, Berlin, Heidelberg, New York, pp. 322-331.

Endress PK, Anliker J. 1968. xSycoparrotia semidecidua hybr. nov. (= Parrotia persica C. A. Mey. x Sycopsis sinensis Oliv.). – Schweiz. Beitr. Dendrol. 16-18: 6-28.

Endress PK, Friis EM. 1991. Archamamelis, hamamelidalean flowers from the Upper Cretaceous of Sweden. – Plant Syst. Evol. 175: 101-114.

Endress PK, Hyland BPM, Tracey JG. 1985. Noahdendron, a new Australian genus of the Hamamelidaceae. – Bot. Jahrb. Syst. 107: 369-378.

Engelmann W. 1960. Endogene Rhythmik und photoperiodische Blühinduktion bei Kalanchoe. – Planta 55: 496-511.

Engler A. 1891. Saxifragaceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(2a), W. Engelmann, Leipzig, pp. 41-93; Engler A. 1897. Nachträge zu III(2a), p. 180.

Engler A. 1930. Saxifragaceae. – In: Engler A, Harms H (eds), Die natürlichen Pflanzenfamilien, 2. Aufl., Bd. 18a, W. Engelmann, Leipzig, pp. 74-226.

Fægri K. 1982. The Myriophyllum spicatum group in North Europe. – Taxon 31: 467-471.

Fairfield KN, Mort ME, Santos-Guerra A. 2004. Phylogenetics and evolution of the Macaronesian members of the genus Aichryson (Crassulaceae) inferred from nuclear and chloroplast sequence data. – Plant Syst. Evol. 248: 71-83.

Favarger C. 1957. Sur deux critères nouveaux utilisables dans la taxinomie des Saxifragacées. – Rev. Cytol. Biol. Vég. 18: 125-137.

Fehrenbach S, Barthlott W. 1988. Mikromorphologie der Epicuticular-Wachse der Rosales s.l. und deren systematische Bedeutung. – Bot. Jahrb. Syst. 109: 407-428.

Feng G-P, Li C-S, Zhilin SG, Wang Y-F, Gabrielyan IG. 2000. Nyssidium jiayinense sp. nov. (Cercidiphyllaceae) of the Early Tertiary from North-East China. – Bot. J. Linn. Soc. 134: 471-484.

Feng Y-X, Chen Z-D, Wang X-Q, Pan K-Y, Hong D-Y. 1999. A taxonomic revision of the Loropetalum-Tetrathyrium complex and its systematic position in the Hamamelidoideae, based on morphology and ITS sequence data. – Taxon 48: 689-700.

Ferguson DK. 1989. A survey of the Liquidambaroideae (Hamamelidaceae) with a view to elucidating its fossil record. – In: Crane PR, Blackmore S (eds), Evolution, systematics, and fossil history of the Hamamelidae 1: Introduction and ‘lower’ Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 249-272.

Ferguson IK, Webb DA. 1970. Pollen morphology in the genus Saxifraga and its taxonomic significance. – Bot. J. Linn. Soc. 63: 295-311.

Fernald ML. 1919. Two new Myriophyllums and a species new to the United States. – Rhodora 21: 120-124.

Fernandes RB. 1978. Crassulaceae africanae novae vel minus cognitae. – Botl. Soc. Brot., Sér. II, 52: 165-220.

Fernandes RB. 1983. 67. Crassulaceae. – In: Launert E (ed), Flora Zambesiaca 7 (Part 1), Flora Zambesiaca Managing Committee, London, pp. 3-74.

Fétré J, Lebègue A. 1964. Embryogénie des Crassulacées. – Compt. Rend. Acad. Sci. Paris 258: 5035-5038.

Fishbein M, Soltis DE. 2004. Further resolution of the rapid radiation of Saxifragales (angiosperms, eudicots) supported by mixed-model Bayesian analysis. – Syst. Bot. 29: 883-891.

Fishbein M, Hibsch-Jetter C, Soltis DE, Hufford L. 2001. Phylogeny of Saxifragales (angiosperms, eudicots): analysis of a rapid, ancient radiation. – Syst. Biol. 50: 817-847.

Folk RA, Freudenstein JV. 2014a. Phylogenetic relationships and character evolution in Heuchera (Saxifragaceae) on the basis of multiple nuclear loci. – Amer. J. Bot. 101: 1532-1550.

Folk RA, Freudenstein JV. 2014b. Revision of Heuchera Section Rhodoheuchera Subsections Hemsleyanae and Rosendahliae Subsectio Nova (Saxifragaceae). – Syst. Bot. 39: 850-8974.

Franchet AR. 1890. Monographie du genre Chrysosplenium Tournefort. – Nouv. Arch. Mus. Natl. Hist. Nat. Paris, sér. III, 2: 87-114.

Freire-Fierro A. 2002. A new species of Ribes (Grossulariaceae), along with notes and a key to the Ecuadorian species. – Syst. Bot. 27: 14-18.

Freire-Fierro A, Romoleroux K. 2004. 73. Crassulaceae, 74. Saxifragaceae, 75B. Grossulariaceae. – In: Harling G, Andersson L (eds), Flora of Ecuador 73, Botanical Institute, Göteborg University, pp. 3-24, 41-66.

Friedrich H-C. 1973. Zur Cytotaxonomie der Gattung Crassula. – Garcia de Orta, Sér. Bot., 1: 49-65.

Friedrich H-C. 1979. Vorarbeiten zu einer Monographie der Gattung Crassula L. 3. Die hydrophylen Sippen in Süd- und Ostafrika. – Mitt. Bot. München 15: 577-598.

Fröderström H. 1930. The genus Sedum L. I. – Acta Horti Gothoburg. 5, Appendix: 1-75.

Fröderström H. 1932a. The genus Sedum L. II. – Acta Horti Gothoburg. 6, Appendix: 1-111.

Fröderström H. 1932b. The genus Sedum L. III. – Acta Horti Gothoburg. 7, Appendix: 1-126.

Fröderström H. 1936. The genus Sedum L. IV. – Acta Horti Gothoburg. 11, Appendix: 1-262.

Fu K-T. 1965. Species et combinationes novae Crassulacearum Sinicarum. – Acta Phytotaxon. Sin. 10: 111-128.

Fu K-T. 1974. Revision of the section Oreades of Chinese Sedum. – Acta Phytotaxon. Sin. 12: 51-77. [In Chinese].

Gandolfo MA, Nixon KC, Crepet WL. 1998. Tylerianthus crossmanensis gen. et sp. nov. (aff. Hydrangeaceae) from the Upper Cretaceous of New Jersey. – Amer. J. Bot. 85: 376-386.

Garcês HMP, Champagne CEM, Townsley BT, Park S, Malhó R, Pedroso MC, Harada JJ, Sinha NR. 2007. Evolution of asexual reproduction in leaves of the genus Kalanchoë. – Proc. Natl. Acad. Sci. U.S.A. 104: 15578-15583.

Gäumann E. 1919. Studien über die Entwicklungsgeschichte einiger Saxifragales. – Rec. Trav. Bot. Néerl. 16: 285-322.

Ge L-P, Lu A-M, Pan K-Y. 2002. Floral ontogeny in Itea yunnanensis (Iteaceae). – Acta Bot. Sin. 44: 1261-1267.

Gehrig H, Gaußmann O, Max H, Schwarzott D, Kluge M. 2001. Molecular phylogeny of the genus Kalanchoe (Crassulaceae) inferred from nucleotide sequences of the ITS-1 and ITS-2 regions. – Plant Sci. 160: 827-835.

Gelius L. 1967. Studien zur Entwicklungsgeschichte an Blüten der Saxifragales sensu lato mit besonderer Berücksichtigung des Androeceums. – Bot. Jahrb. Syst. 87: 253-303.

George G, Candela C, Quinet M, Fellous R. 1974. Identification of the diterpenic acid of Ribes nigrum buds. – Helv. Chim. Acta 57: 1247-1249.

Gess S, Gess F, Gess R. 1998. Birds, wasps and Tylecodon. Pollination strategies of two members of the genus Tylecodon in Namaqualand. – Veld and Flora 84: 56-57.

Gilbert MG. 1985. The genus Sedum in Ethiopia. – Bradleya 3: 48-52.

Gluchoff-Fiasson K, Fenet B, Leclerc J-C, Reynaud J, Lussignol M, Jay M. 2001. Three new flavonol malonylrhamnosides from Ribes alpinum. – Chem. Pharmaceut. Bull. 49: 768-770.

Goldblatt P, Endress PK. 1977. Cytology and evolution in Hamamelidaceae. – J. Arnold Arbor. 58: 67-71.

Goldschmidt E. 1964. Cytological species and interspecific hybrids of the genus Ribes. – Hereditas 52: 139-150.

Gontcharova SB. 1999. Ornamentation of the testa of some Eastern Asian Sedoideae (Crassulaceae). – Bull. Natl. Sci. Mus., Tokyo, ser. B, 25: 131-141.

Gontcharova SB, Artiukova EV, Gontcharov AA. 2006. Phylogenetic relationships among members of the subfamily Sedoideae (Crassulaceae) inferred from the ITS region sequences of nuclear rDNA. – Genetika 42: 803-811.

Gorenflot R, Moreau F. 1970. Types stomatiques et phylogénie des Saxifraginées (Saxifragacées). – Compt. Rend. Acad. Sci. Paris 270: 2802-2805.

Gornall RJ. 1980. Generic limits and systematics of Boykinia and allies (Saxifragaceae). – Ph.D. diss., University of British Columbia, Vancouver, British Columbia.

Gornall RJ. 1986. Trichome anatomy and the taxonomy of Saxifraga (Saxifragaceae). – Nord. J. Bot. 6: 257-275.

Gornall RJ. 1987a. An outline of a revised classification of Saxifraga L. – Bot. J. Linn. Soc. 95: 273-292.

Gornall RJ. 1987b. Foliar crystals in Saxifraga and segregate genera (Saxifragaceae). – Nord. J. Bot. 7: 233-238.

Gornall RJ. 1989. Anatomical evidence and the taxonomic position of Darmera (Saxifragaceae). – Bot. J. Linn. Soc. 100: 173-182.

Gornall RJ, Bohm BA. 1980. The use of flavonoids in the taxonomy of Boykinia and allies (Saxifragaceae). – Can. J. Bot. 58: 1768-1779.

Gornall RJ, Bohm BA. 1984. Breeding systems and relationships among species of Boykinia and related genera (Saxifragaceae). – Can. J. Bot. 62: 33-37.

Gornall RJ, Bohm BA. 1985. A monograph of Boykinia, Peltoboykinia, Bolandra, and Suksdorfia (Saxifragaceae). – Bot. J. Linn. Soc. 90: 1-71.

Gornall RJ, Bohm BA. Taylor RL. 1983. Chromosome numbers in Boykinia and allies (Saxifragaceae). – Can. J. Bot. 61: 1979-1982.

Gruas-Cavagnetto C, Praglowski J. 1977. Pollen d’Haloragacées dans le Thanétien et le Cuisien du basin de Paris. – Pollen Spores 19: 299-308.

Gruhlich V. 1984. Generic division of Sedoideae in Europe and adjacent regions. – Preslia 56: 29-54.

Grund C, Jensen U. 1981. Systematic relationships of the Saxifragales revealed by serological characteristics of seed proteins. – Plant Syst. Evol. 137: 1-22.

Günthart A. 1902. Beiträge zur Blütenbiologie der Cruciferen, Crassulaceen und der Gattung Saxifraga. – Bibl. Bot. 58: 1-97.

Guzmán JM, Gordillo MM, Durán RC, Ramírez JJ, Pérez-Amador MC. 2013. A synopsis of Pterostemon (Iteaceae), a group endemic to Mexico. – Amer. J. Plant Sci. 4: 1-9.

Hallier H. 1904. Über die Gattung Daphniphyllum, ein Übergangsglied von den Magnoliaceen und Hamamelidaceen zu den Kätzchenblütlern. – Bot. Mag. (Tokyo) 18: 55-69.

Ham RCHJ van. 1994. Phylogenetic implications of chloroplast DNA variation in the Crassulaceae. – Ph.D. diss., Universiteit Utrecht, The Netherlands.

Ham RCHJ van. 1995. Phylogenetic relationships in the Crassulaceae inferred from chloroplast DNA variation. – In: Hart H ‘t, Eggli U (eds), Evolution and Systematics of the Crassulaceae, Backhuys, Leiden, pp. 17-29.

Ham RCHJ van, Hart H ’t. 1994. Evolution of Sedum series Rupestria (Crassulaceae): evidence from chloroplast DNA and biosystematic data. – Plant Syst. Evol. 190: 1-20.

Ham RCHJ van, ‘t Hart H. 1998. Phylogenetic relationships in the Crassulaceae inferred from chloroplast DNA restriction-site variation. – Amer. J. Bot. 85: 123-134.

Ham RCHJ van, ‘t Hart H, Mes THM, Sandbrink JM. 1994. Molecular evolution of noncoding regions of the chloroplast genome in the Crassulaceae and related species. – Curr. Genet. 25: 558-566.

Hamel J. 1953. Contribution à l’étude cytotaxinomique des Saxifragacées. – Rev. Cytol. Biol. Vég. 14: 113-311.

Hamet R. 1929. Contribution à l’étude phytogéographique du genre Sedum. – Candollea 4: 1-52.

Hara H. 1957. Synopsis of the genus Chrysosplenium L. (Saxifragaceae). – J. Fac. Sci. Univ. Tokyo, Sect. III, Bot. 7: 1-90.

Harms H. 1916. Über die Blütenverhältnisse und die systematische Stellung der Gattung Cercidiphyllum Sieb. et Zucc. – Ber. Deutsch. Bot. Ges. 34: 272-283.

Harms H. 1930. Hamamelidaceae. – In: Engler A, Harms H (eds), Die natürlichen Pflanzenfamilien, 2. Aufl., Bd. 18a, W. Engelmann, Leipzig, pp. 303-345, 487.

Harmsen L. 1939. Studies in the embryology and cytology of Saxifraga. – Medd. Grønl. 125: 1-15.

Hart H ‘t. 1972. Chromosome numbers in the series Rupestria Berger of the genus Sedum L. – Acta Bot. Neerl. 21: 428-435.

Hart H ‘t. 1975. The pollen morphology of 24 European species of the genus Sedum L. – Pollen Spores 16: 373-387.

Hart H ‘t. 1978. Biosystematic studies in the Acre group and the series Rupestria Berger of the genus Sedum L. (Crassulaceae). – Ph.D. diss., Universiteit Utrecht, The Netherlands.

Hart H ‘t. 1982a. The systematic position of Sedum tuberosum Coss. & Let. (Crassulaceae). – Proc. Kon. Nederl. Akad. Wet., Ser. C, 85: 497-508.

Hart H ‘t. 1982b. The white-flowered European Sedum species 1. Principles of a phylogenetic classification of the Sedoideae (Crassulaceae) and the position of the white-flowered Sedum species. – Proc. Kon. Nederl. Akad. Wet., Ser. C, 85: 663-675.

Hart H ‘t. 1985a. Sexual reproduction and hybridisation in Sedum telephium (Crassulaceae). – Acta Bot. Neerl. 34: 1-4.

Hart H ‘t. 1985b. The vascular pattern of the flowers of Sedum anacampseros (Crassulaceae). – Acta Bot. Neerl. 34: 119-121.

Hart H ‘t. 1985c. Chromosome numbers in Sedum (Crassulaceae) from Greece. – Willdenowia 15: 115-135.

Hart H ‘t. 1987a. Natural hybrids in Sedum (Crassulaceae) 1. Two new hybrids of S. series Rupestria and a new locality of S. x brevierei. – Bot. Jahrb. Syst. 109: 1-16.

Hart H ‘t. 1987b. Evolution of the Eurasiatic Sedum flora. – I.O.S. Bull. 4: 209-210.

Hart H ‘t. 1990. Variation in the structure of the flowers of Sedum. – Sedum Soc. Newslett. 13: 11-17.

Hart H ‘t. 1991. Evolution and classification of the European Sedum species (Crassulaceae). – Flora Mediterr. 1, OPTIMA, Madrid, pp. 31-61.

Hart H ‘t. 1992. The archetype of the Crassulaceae. – Acta Bot. Neerl. 41: 107-108.

Hart H ‘t. 1994a. The evolution of life-forms, growth-forms and secondary growth in Eurasian Sedoideae (Crassulaceae). – Bradleya 12: 37-56.

Hart H ‘t. 1994b. The unilacunar two-trace nodal structure of the caudex of Rhodiola rosea L. (Crassulaceae). – Bot. J. Linn. Soc. 116: 235-241.

Hart H ‘t. 1995. Infrafamilial and generic classification of the Crassulaceae. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys, Leiden, pp. 159-172.

Hart H ‘t. 1997. Diversity within Mediterranean Crassulaceae. – Lagascalia 19: 93-100.

Hart H ‘t, Alpinar K. 1991. Biosystematic studies in Sedum (Crassulaceae) of Turkey 1. Notes on four hitherto little known species collected in the western part of Anatolia. – Willdenowia 21: 143-156.

Hart H ‘t, Alpinar K. 1999. Sedum ince (Crassulaceae), a new species from southern Anatolia. – Edinburgh J. Bot. 56: 181-194.

Hart H ‘t, Arkel J van. 1985. Quantitative aspects of the influence of day-length and temperature on Sedum telephium (Crassulaceae). – Acta Bot. Neerl. 34: 115-118.

Hart H ’t, Berendsen W. 1980. Ornamentation of the testa in Sedum (Crassulaceae). – Plant Syst. Evol. 135: 107-117.

Hart H ‘t, Berg AJJ van den 1982. The white-flowered European Sedum species 2. Cytotaxonomic notes on S. album L. and S. gypsicolum Boiss. & Reuter. – Proc. Kon. Nederl. Akad. Wet., Ser. C, 85: 677-691.

Hart H ‘t, Bleij B. 1999. Nieuwe namen in Sempervivum Sect. Jovibarba (Crassulaceae). – Succulenta 78: 35-42.

Hart H ‘t, Eggli U. 1995a. Introduction: evolution of Crassulaceae systematics. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys Publ., Leiden, The Netherlands, pp. 7-15.

Hart H ‘t, Eggli U (eds). 1995b. Evolution and systematics of the Crassulaceae. – Backhuys Publ., Leiden, The Netherlands.

Hart H ‘t, Eggli U. 1998. Cytotaxonomic studies in Rosularia (Crassulaceae). – Bot. Helvetica 98: 223-234.

Hart H ‘t, Koek-Noorman J. 1989. The origin of the woody Sedoideae (Crassulaceae). – Taxon 38: 535-544.

Hart H ’t, Sandbrink JM, Csikos I, Ooyen A, Brederode J van. 1993. Natural hybrids in Sedum (Crassulaceae) 4. The allopolyploid origin of Sedum rupestre subsp. rupestre (Crassulaceae). – Plant Syst. Evol. 184: 195-206.

Hart H ’t, Ham RDHJ van, Stevens JF, Elema ET, Klis H van, Gadella TWJ. 1999. Biosystematic, molecular and phytochemical evidence for the multiple origin of sympetaly in Eurasian Sedoideae (Crassulaceae). – Biochem. Syst. Ecol. 27: 407-426.

Haskins ML, Hayden WJ. 1987. Anatomy and affinities of Penthorum. – Amer. J. Bot. 74: 164-177.

Hayden WJ, Lewandowski JD. 1997. Gynoecium structure in Penthorum. – Amer. J. Bot. 84: 201.

Hébert LP. 1975. Contribution à la cytotaxonomie du genre Sedum L. – Bull. Soc. Neuchât., Sci. Nat. 98: 59-70.

Hébert LP. 1976. Nouvelle contribution à la cytotaxonomie du genre Sedum L. – Bull. Soc. Neuchât., Sci. Nat. 99: 97-107.

Hébert LP. 1983. Analyse d’un complexe chromosomique en Mediterranée: Sedum ser. Rupestria Berger emend. – Rev. Cytol. Biol. Végét. Bot. 6: 179-224.

Heel WA van. 1986. A deviating female flower of Cercidiphyllum japonicum (Cercidiphyllaceae). – Blumea 31: 273-276.

Heel WA van. 1987. Note on the morphology of the male inflorescences in Cercidiphyllum (Cercidiphyllaceae). – Blumea 32: 303-309.

Henry JK. 1919. Ribes divaricatum x Ribes lobbii. – Can. Field-Natur. 19: 94.

Hermsen EJ, Gandolfo MA, Nixon KC, Crepet WL. 2003. Divisestylus gen. nov. (aff. Iteaceae), a fossil saxifrage from the late Cretaceous of New Jersey, USA. – Amer. J. Bot. 90: 1373-1383.

Hermsen EJ, Nixon KC, Crepet WL. 2006. The impact of extinct taxa on understanding the early evolution of angiosperm clades: an example incorporating fossil reproductive structures of Saxifragales. – Plant Syst. Evol. 260: 141-169.

Hernández E, Bañares A. 1996. Aeonium volkeri sp. nov., nuevo endemiso de la isla de Tenerife, islas Canárias (Crassulaceae). – Vieraea 25: 159-168.

Hernández-Castillo GR, Cevallos-Ferriz SRS. 1999. Reproductive and vegetative organs with affinities to Haloragaceae from the Upper Cretaceous Huepac Chert locality of Sonora, Mexico. – Amer. J. Bot. 86: 1717-1734.

Herr JM. 1954. The development of the ovule and female gametophyte in Tiarella cordifolia. – Amer. J. Bot. 41: 333-338.

Hewson HJ. 1989. Hamamelidaceae. – In: George AS (ed), Flora of Australia 3, Australian Government Publ. Service, Canberra, pp. 1-4.

Hideux M. 1981. Le pollen données nouvelles de la microscopie électronique et de l’informatique. Structure du sporoderme de Rosidae-Saxifragales, étude comparative et dynamique. – Agence de Coopération Culturelle et Technique, Paris.

Hideux M, Abadie M. 1985. Cytologie ultrastructurale de l’anthère de Saxifraga I. Période d’initiation des précurseurs des sporopollénines au niveau des principaux types exiniques. – Can. J. Bot. 63: 97-112.

Hideux M, Ferguson IK. 1976. The stereostructure of the exine and its evolutionary significance in Saxifragaceae sensu lato. – In: Ferguson IK, Muller J (eds), The evolutionary significance of the exine, Linn. Soc. Symposium, No. 1, Academic Press, London and New York, pp. 327-377.

Hiepko P. 1965. Das zentrifugale Androecium der Paeoniaceae. – Ber. Deutsch. Bot. Ges. 77: 427-435.

Hiepko P. 1966. Zur Morphologie, Anatomie und Funktion des Diskus der Paeoniaceae. – Ber. Deutsch. Bot. Ges. 79: 233-245.

Hils MH. 1985. Comparative anatomy and systematics of twelve woody Australasian genera of the Saxifragaceae. – Ph.D. diss., University of Florida, Gainesville, Florida.

Hils MH, Dickison WC, Lucansky TW, Stern WL. 1988. Comparative anatomy and systematics of woody Saxifragaceae: Tetracarpaea. – Amer. J. Bot. 75: 1687-1700.

Hoey MT, Parks CR. 1991. Isozyme divergence between eastern Asian, North American, and Turkish species of Liquidambar (Hamamelidaceae). – Amer. J. Bot. 78: 938-947.

Hoey MT, Parks CR. 1994. Genetic divergence in Liquidambar styraciflua, L. formosana, and L. acalycina (Hamamelidaceae). – Syst. Bot. 19: 308-316.

Holderegger R. 1996. Reproduction of the rare monocarpic species Saxifraga mutata L. – Bot. J. Linn. Soc. 122: 301-313.

Holderegger R, Abbott RJ. 2003. Phylogeography of the arctic-alpine Saxifraga oppositifolia (Saxifragaceae) and some related taxa based on cpDNA and ITS sequence variation. – Amer. J. Bot. 90: 931-936.

Holle G. 1893. Beiträge zur Anatomie der Saxifragaceen und deren systematische Verwerthung. – Bot. Centralbl. 53: 1-9, 33-41, 65-70, 97-102, 129-136, 161-169, 209-222.

Hong D-Y. 1989. Studies on the genus Paeonia 2. The characters of leaf epidermis and their systematic significance. – Chinese J. Bot. 1: 145-154.

Hong D-Y, Zhou S-L. 2003. Paeonia (Paeoniaceae) in the Caucasus. – Bot. J. Linn. Soc. 143: 135-150.

Hong D-Y, Zhang Z-X, Zhu X-Y. 1988. Studies on the genus Paeonia 1. Report of karyotypes of some wild species in China. – Acta Phytotaxon. Sin. 26: 33-43. [In Chinese]

Hong D-Y, Pan K-Y, Rao G-Y. 2001. Cytogeography and taxonomy of the Paeonia obovata polyploid complex (Paeoniaceae). – Plant Syst. Evol. 227: 123-136.

Hong D-Y, Wang X-Q, Zhang D-M. 2004. Paeonia saueri (Paeoniaceae), a new species from the Balkans. – Taxon 53: 83-90.

Hong D-Y, Zhang D-M, Wang X-Q, Koruklu ST, Tzanoudakis D. 2008. Relationships and taxonomy of Paeonia arietina G. Anderson complex (Paeoniaceae) and its allies. – Taxon 57: 922-932.

Horne AL. 1914. A contribution to the study of the evolution of the flower, with special reference to the Hamamelidaceae, Caprifoliaceae, and Cornaceae. – Trans. Linn. Soc. London, Bot., 2nd ser., 8: 239-309.

Huang G-L. 1986. Comparative anatomical studies on the woods of Hamamelidaceae in China. – Acta Sci. Nat. Univ. Sunyatsenia 1986, 1: 22-28. [In Chinese with English summary]

Huang G-L, Lee C-L. 1982. Anatomical studies of Chunia wood. – Acta Bot. Sin. 24: 506-511. [In Chinese]

Huang T-C. 1965. Monograph of Daphniphyllum, I. – Taiwania 11: 57-98.

Huang T-C. 1966. Monograph of Daphniphyllum, II. – Taiwania 12: 137-234.

Huang T-C. 1996. Notes on taxonomy and pollen of Malesian Daphniphyllum (Daphniphyllaceae). – Blumea 41: 231-244.

Huang T-C. 1997. Daphniphyllaceae. – In: Kalkman C et al. (eds), Flora Malesiana, I, 13, Flora Malesiana Foundation, Rijksherbarium/Hortus Botanicus, Leiden, pp. 145-168.

Hufford L, Crane PR. 1989. A preliminary phylogenetic analysis of the ‘lower’ Hamamelidae. – In: Crane PR, Blackmore S (eds), Evolution, systematics and fossil history of the Hamamelidae 1: Introduction and ‘lower’ Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 175-192.

Ickert-Bond SM, Wen J. 2006. Phylogeny and biogeography of Altingiaceae: evidence from combined analysis of five non-coding chloroplast regions. – Mol. Phylogen. Evol. 39: 512-528.

Ickert-Bond SM, Pigg KB, Wen J. 2005. Comparative infructescence morphology in Liquidambar (Altingiaceae) and its evolutionary significance. – Amer. J. Bot. 92: 1234-1255.

Ickert-Bond SM, Pigg KB, Wen J. 2007. Comparative infructescence morphology in Altingia (Altingiaceae) and discordance between morphological and molecular phylogenies. – Amer. J. Bot. 94: 1094-1115.

Ignat’eva IP. 1995. Ontogenetic morphogenesis in vegetative organs of peony (Paeonia anomala L.). – Izvestiya TCXA 4: 108-134. [In Russian]

Ikeda H, Itoh K. 2001. Germination and water dispersal of seeds from a threatened plant species, Penthorum chinense. – Ecol. Res. 16: 99-106.

Jaarsveld EJ van. 1994. The distribution of Tylecodon and Cotyledon (Crassulaceae) in South Africa and Namibia. – In: Seyani JH, Chikuni AC (eds), Proc. XIII Plenary Meeting AETFAT, Malawi, pp. 1157-1163.

Jacobsen V. 1954. Handbuch der sukkulenten Pflanzen 2. – Gustav Fischer, Jena.

Jäger-Zúrn I. 1989. Zur Kenntnis von Crassula pageae Tölken (syn. Pagella archeri). – Trop.-Subtrop. Pflanzenwelt 70: 1-71

Jähnichen H, Mai DH, Walther H. 1980. Blätter und Früchte von Cercidiphyllum Siebold et Zuccarini im mitteleuropäischen Tertiär. – Schriftenr. Geol. Wiss. 16: 357-399.

Janczewski E de. 1906a. Species generis Ribes L. II. Subgenera Ribesia et Coreosma. – Bull. Int. Acad. Polon. Sci., Cl. Sci. Math., Sér. B, Sci. Nat. 1906: 1-13.

Janczewski E de. 1906b. Species generis Ribes L. III. Subgenera Grossularioides, Grossularia, et Berisia. – Bull. Int. Acad. Polon. Sci., Cl. Sci. Math., Sér. B, Sci. Nat. 1906: 280-293.

Janczewski E de. 1907. Monographie des groseilliers, Ribes L. – Mém. Soc. Phys. Genève 35: 199-517.

Jay M. 1967. Recherches chimiotaxinomiques sur les plantes vasculaires 1. Distribution des flavonoides chez les Saxifragacées. – Compt. Rend. Acad. Sci. Paris 264: 1754-1756.

Jay M. 1968. Distribution des flavonoides chez les Hamamelidacées et familles affines. – Taxon 17: 136-147.

Jay M. 1969. Contribution biochimique à la connaissance taxonomique et phylogénetique des Saxifragacées et familles affinés. – Ph.D. diss., l’Université de Lyon, France.

Jay M. 1971. Quelques problèmes taxinomiques et phylogénétiques des Saxifragacées vus à la lumière de la biochimie flavonique. – Bull. Mus. Natl. Hist. Nat. Paris, sér. II, 42: 754-775.

Jay M, Voirin B. 1976. Les flavonoides de deux espèces du genre Chrysosplenium. – Phytochemistry 15: 517-519.

Jensen LCW. 1966. Comparative anatomical studies in three subfamilies of the Crassulaceae. – Ph.D. diss., University of Minnesota, Minneapolis, Minnesota.

Jensen LCW. 1968. Primary stem vascular patterns in three subfamilies of the Crassulaceae. – Amer. J. Bot. 55: 553-563.

Jha UN. 1978. Chemotaxonomy of the Hamamelidaceae. – J. Indian Bot. Soc. 56: 44-48.

Jian S, Soltis PS, Gitzendanner MA, Moore MJ, Li R, Hendry TA, Qiu Y-L, Dhingra A, Bell C, Soltis DE. 2008. Resolving an ancient, rapid radiation in Saxifragales. – Syst. Biol. 57: 38-57.

Johnson AM. 1923. A revision of the North American species of the section Boraphila Engler of the genus Saxifraga (Tourn.) L. – Univ. Minnesota Stud. Biol. Sci. 4: 1-109.

Johnson AM. 1927. The status of Saxifraga nuttallii. – Amer. J. Bot. 14: 38-43.

Johnson LA, Soltis DE. 1994. matK DNA sequences and phylogenetic reconstruction in Saxifragaceae s. str. – Syst. Bot. 19: 143-156.

Johnson LA, Soltis DE. 1995. Phylogenetic inference in Saxifragaceae sensu stricto and Gilia (Polemoniaceae) using matK sequences. – Ann. Missouri Bot. Gard. 82: 149-175.

Johnson SD, Ellis A, Carrick P, Swift P, Horner N, Janse van Rensburg S, Bond WJ. 1993. Moth pollination and rhythms of advertisement and reward in Crassula fascicularis (Crassulaceae). – South Afr. J. Bot. 59: 511-513.

Jørgensen MH, Elven R, Tribsch A, Gabrielsen, Stedje B, Brochmann C. 2006. Taxonomy and evolutionary relationships in the Saxifraga rivularis complex. – Syst. Bot. 31: 702-729.

Jørgensen TH, Frydenberg J. 1999. Diversification in insular plants; inferring the phylogenetic relationship in Aeonium (Crassulaceae) using ITS sequences of nuclear ribosomal DNA. – Nord. J. Bot. 19: 613-621.

Jørgensen TH, Olesen JM. 2000. Growth rules based on the modularity of the Canarian Aeonium (Crassulaceae) and their phylogenetic value. – Bot. J. Linn. Soc. 132: 223-240.

Jørgensen TH, Olesen JM. 2001. Adaptive radiation of island plants: evidence from Aeonium (Crassulaceae) of the Canary Islands. – Perspect. Plant Ecol. Evol. Syst. 4: 29-42.

Judd WS. Soltis DE, Soltis PS, Ionta G. 2007. Tolmiea diplomenziesii: a new species from the Pacific Northwest and the diploid sister taxon of the autotetraploid T. menziesii (Saxifragaceae). – Brittonia 59: 217-225.

Juel HO. 1907. Studien über die Entwicklungsgeschichte von Saxifraga granulata. – Nova Acta Reg. Soc. Sci. Upsal. 4(1): 1-41.

Jürgens N. 1995. Contributions to the phytogeography of Crassula. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys, Leiden, pp. 136-150.

Kapil RN, Bawa SB. 1968. Embryological studies on the Haloragidaceae I. Haloragis colensoi Skottsb. – Bot. Not. 121: 11-28.

Kapil RN, Kaul U. 1974. Embryologically little known taxon – Parrotiopsis jacquemontiana. – Phytomorphology 22: 234-245.

Kaplan K. 1981. Embryologische, pollen- und samenmorphologische Untersuchungen zur Systematik von Saxifraga (Saxifragaceae). – Bibl. Bot. 134: 1-54.

Kaplan K, Strohschneider M. 1984. Mikromorphologische Untersuchungen an Samenoberflächen in der Gattung Chrysosplenium (Saxifragaceae). – Bot. Jahrb. Syst. 104: 469-482.

Kaul U, Kapil RN. 1974. Exbucklandia populnea: from flower to fruit. – Phytomorphology 24: 217-228.

Keefe JM, Moseley MF Jr. 1978. Wood anatomy and phylogeny of Paeonia section Moutan. – J. Arnold Arbor. 59: 274-297.

Keep E. 1962. Interspecific hybridization in Ribes. – Genetica 33: 1-23.

Keep E. 1975. Currants and gooseberries. – In: Janick J, Moore JN (eds), Advances in fruit breeding, Purdue University Press, West Lafayette Indian, pp. 197-268.

Kern P. 1966. The genus Tiarella in western North America. – Madroño 18: 152-160.

Kim J-H. 1994. Pollen morphology of genus Sedum in Korea. – J. Plant Biol. 37: 245-252.

Kim J-H, Hart H ‘t, Mes THM. 1996. The phylogenetic position of East Asian Sedum species (Crassulaceae) based on chloroplast DNA trnL (UAA) – trnF (GAA) intergenic spacer sequence variation. – Acta Bot. Neerl. 45: 309-321.

Kimnach M. 1978. Sedum suaveolens, a remarkable new species from Durango, Mexico. – Cact. Succ. J. 50: 3-7.

Klopfer K. 1968. Beiträge zur floralen Morphogenese und Histogenese der Saxifragaceae 1. Die Infloreszenz-Entwicklung von Tellima grandiflora. – Flora 157: 461-476.

Klopfer K. 1968. Beiträge zur floralen Morphogenese und Histogenese der Saxifragaceae 2. Die Blütenentwicklung von Tellima grandiflora. – Flora 158: 1-21.

Klopfer K. 1970. Beiträge zur floralen Morphogenese und Histogenese der Saxifragaceae 4. Die Blütenentwicklung einiger Saxifraga-Arten. – Flora 159: 347-365.

Klopfer K. 1973. Florale Morphogenese und Taxonomie der Saxifragaceae sensu lato. – Feddes Repert. 84: 475-516.

Kluge M, Brulfert J. 1996. Crassulacean acid metabolism in the genus Kalanchoë: ecological, physiological and biochemical aspects. – In: Winter K, Smith AP, Smith JAC (eds), Crassulacean acid metabolism. Biochemistry, ecophysiology and evolution, Springer, Berlin, Heidelberg, New York, pp. 324-335.

Knaben G. 1954. Saxifraga osloensis n. sp., a tetraploid species of the Tridactylites section. – Nytt Mag. Bot. 3: 117-138.

Knapp U. 1994. Skulptur der Samenschale und Gliederung der Crassulaceae. – Bot. Jahrb. Syst. 116: 157-187.

Knapp U. 1997. Samenoberfläche und Systematik der Saxifragaceae und Crassulaceae. – Ph.D. diss., Universität Kaiserslautern, Germany.

Köhlein F. 1980. Saxifragen und andere Steinbrechgewächse. – Eugen Ulmer GmbH, Stuttgart.

Kozieradzka-Kiszkurno M, Plachno BJ, Bohdanowicz J. 2011. Are unusual plasmodesmata in the embryo-suspensor restricted to species from the genus Sedum among Crassulaceae? – Flora 206: 684-690.

Kozyrenko MM, Gontcharova SB, Gontcharov AA. 2013. Phylogenetic relationships among Orostachys subsection Orostachys species (Crassulaceae) based on nuclear and chloroplast DNA data. – J. Syst. Evol. 51: 578-589.

Krach JE. 1976. Samenanatomie der Rosifloren I. Die Samen der Saxifragaceae. – Bot. Jahrb. Syst. 97: 1-60.

Krach JE. 1977. Seed characters in and affinities among the Saxifragineae. – In: Kubitzki K (ed), Flowering plants – Evolution and classification at higher categories, Plant Syst. Evol. [Suppl.] 1: 141-153.

Kubitzki K. 2006a. Aphanopetalaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 29-30.

Kubitzki K. 2006b. Daphniphyllaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 127-128.

Kubitzki K. 2006c. Haloragaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 184-190.

Kubitzki K. 2006d. Iteaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 202-204.

Kubitzki K. 2006e. Pterostemonaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 405-406.

Kubitzki K. 2006f. Tetracarpaeaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 456-457.

Kuhlmann JG. 1947. Peridiscaceae (Kuhlmann). – Arq. Serv. Florestal 3: 3-5.

Kumazawa M. 1935. The structure and affinities of Paeonia. – Bot. Mag. (Tokyo) 49: 306-315. [In Japanese]

Küpfer P, Rais JR. 1983. Index des nombres chromosomiques de spermatophytes de la Suisse I. Saxifragaceae. – Bot. Helvetica 93: 11-25.

Kurita M. 1959. Chromosome studies in Ranunculaceae XII. Satellites on the Paeonia chromosomes. – Rep. Biol. Inst. Ehime Univ. 8: 7-11.

Kurkin VA, Zapesochnaya GG. 1986. The chemical composition and pharmacological properties of Rhodiola plants. – Khim-farm. Žurn. 20: 1231-1244. [In Russian]

Kuzoff RK, Soltis DE, Hufford L, Soltis PS. 2000. Phylogenetic relationships within Lithophragma (Saxifragaceae): hybridization, allopolyploidy, and ovary diversification. – Syst. Bot. 24: 598-615.

Kuzoff RK, Hufford L, Soltis DE. 2001. Structural homology and developmental transformations associated with ovary diversification in Lithophragma (Saxifragaceae). – Amer. J. Bot. 88: 196-205.

Lakela O. 1937. A monograph of the genus Tiarella L. in North America. – Amer. J. Bot. 24: 344-351.

Leinfellner W. 1954. Beiträge zur Kronblattmorphologie III. Die Kronblätter der Gattung Pachyphytum. – Österr. Bot. Zeitschr. 101: 586-591.

Le Lous J, Majoie B, Morinière JL, Wulfert E. 1975. Study of the flavonoids of Ribes nigrum. – Ann. Pharmaceut. Franç. 33: 393-399.

Lems K. 1960. Botanical notes on the Canary Islands II. The evolution of plant forms in the islands: Aeonium. – Ecology 41: 1-17.

Lercker G, Cocchi M, Turchetto E. 1988. Ribes nigrum seed oil. – Riv. Ital. Sost. Grasse 65(1): 1-6.

Leroy JE. 1980. Développement et organogenèse chez le Cercidiphyllum japonicum: un cas semblant unique chez les Angiospermes. – Compt. Rend. Acad. Sci. Paris., sér. D, 290: 679-682.

Levin GA, Mulroy TW. 1985. Floral morphology, nectar production, and breeding systems in Dudleya subgenus Dudleya (Crassulaceae). – Trans. San Diego Soc. Nat. Hist. 21: 57-70.

Li H-M, Hickey LJ. 1988. Leaf architecture and systematics of the Hamamelidaceae sensu lato. – Acta Phytotaxon. Sin. 26: 96-110. [In Chinese]

Li J-H. 1997. Systematics of the Hamamelidaceae based on morphological and molecular evidence. – Ph.D. diss., University of New Hampshire, Durham, New Hampshire.

Li J-H, Bogle AL. 2001. A new suprageneric classification system of Hamamelidoideae based on morphology and sequences of nuclear and chloroplast DNA. – Harvard Pap. Bot. 5: 499-515.

Li J-H, Donoghue MJ. 1999. More molecular evidence for interspecific relationships in Liquidambar (Hamamelidaceae). – Rhodora 101: 87-91.

Li J-H, Bogle AL, Klein AS, Pan KY. 1997. Close relationship between Shaniodendron and Parrotia (Hamamelidaceae), evidence from ITS sequences of nuclear ribosomal DNA. – Acta Phytotaxon. Sin. 35: 481-493.

Li J-H, Bogle AL, Klein AS. 1998. Phylogenetic relationships in the Corylopsis complex (Hamamelidaceae) based on sequences of the internal transcribed spacers of nuclear ribosomal DNA and morphology. – Rhodora 99: 302-318.

Li J-H, Bogle AL, Klein AS, Donoghue MJ. 2000. Phylogeny and biogeography of Hamamelis (Hamamelidaceae). – Harvard Pap. Bot. 5: 171-178.

Li J-M, Hickey LJ. 1988. Leaf architecture and systematics of the Hamamelidaceae sensu lato. – Acta Phytotaxon. Sin. 27: 96-110.

Li J, Bogle AL. 2001. A new suprageneric classification system of Hamamelidoideae based on morphology and sequences of nuclear and chloroplast DNA. – Harvard Pap. Bot. 5: 499-515.

Li J, Bogle AL, Klein AS. 1999a. Phylogenetic relationships of the Hamamelidaceae inferred from sequences of internal transcribed spacers (ITS) of nuclear ribosomal DNA. – Amer. J. Bot. 86: 1027-1037.

Li J, Bogle AL, Klein AS. 1999b. Phylogenetic relationships of the Hamamelidaceae: evidence from the nucleotide sequences of the plastid gene matK. – Plant Syst. Evol. 218: 205-219.

Liu H-Y. 1989. Systematics of Aeonium (Crassulaceae). – National Museum of Natural Science, Taichung, Taiwan, Spec. Publ. No. 3: 1-102.

Lösch R. 1990. Funktionelle Voraussetzungen der adaptiven Nischenbesetzung in der Evolution der makaronesischen Semperviven. – Diss. Bot. 146: 1-482.

Lozano-Contreras G. 1996. Hallazgo de la familia Hamamelidaceae en suramérica y descripción de una nueva especie de Matudaea de Colombia. – Rev. Acad. Colombiana Ci. Exact. Físic. Natur. 20: 443-445.

Lu Y-R, Foo L-Y, Wong H. 2002. Nigrumin-5-p-coumarate and nigrumin-5-ferulate, two unusial nitrile-containing metabolites from black currant (Ribes nigrum) seed. – Phytochemistry 59: 465-468.

Luizet D. 1913. Classification naturelle des saxifrages de la section Dactyloides Tausch. – Rev. Gén. Bot. 25: 273-284.

Magallón SA. 2007. From fossils to molecules: phylogeny and the core eudicot floral groundplan in Hamamelidoideae (Hamamelidaceae, Saxifragales). – Syst. Bot. 32: 317-347.

Magallón SA, Crane PR, Herendeen PS. 1999. Phylogenetic pattern, diversity, and diversification of eudicots. – Ann. Missouri Bot.Gard. 86: 297-372.

Magallón SA, Herendeen PS, Crane PR. 2001. Androdecidua endressii gen. et sp. nov. from the Late Cretaceous of Georgia (United States): further floral diversity in Hamamelidoideae (Hamamelidaceae). – Intern. J. Plant Sci. 162: 963-983.

Magallón-Puebla S, Herendeen PS, Endress PK. 1996. Allonia decandra: flora remains of the tribe Hamamelideae (Hamamelidaceae) from Campanian strata of Southeastern USA. – Plant Syst. Evol. 202: 177-198.

Mai DH. 1985. Beiträge zur Geschichte einiger holziger Saxifragales-Gattungen. – Gleditschia 13: 75-88.

Mai DH. 2001. The fossils of Rhodoleia champion (Hamamelidaceae) in Europe. – Acta Palaeobot. 41: 161-175.

Manheim BS Jr, Mulroy TW, Hogness DK, Kerwin JL. 1979. Interspecific variation in leaf wax of Dudleya. – Biochem. Syst. Ecol. 7: 17-19.

Manos PS, Steele KP. 1997. Phylogenetic analyses of ”higher” Hamamelididae based on plastid sequence data. – Amer. J. Bot. 84: 1407-1419.

Manos PS, Nixon KC, Doyle JJ. 1993. Cladistic analysis of restriction site variation within the chloroplast DNA inverted repeat region of selected Hamamelididae. – Syst. Bot. 18: 551-562.

Marchant TA, Alarcon R, Simonsen JA, Koopowitz H. 1998. Population ecology of Dudleya multicaulis (Crassulaceae): a rare narrow endemic. – Madroño 45: 215-220.

Martin CE, Willert DJ von. 2000. Leaf epidermal hydathodes and the ecophysiological consequences of foliar water uptake in species of Crassula from the Namib desert in Southern Africa. – Plant Biol. 2: 229-242.

Maslova NP. 2003. Extinct and extant Platanaceae and Hamamelidaceae: morphology, systematics, and phylogeny. – Paleontol. J. 37(Suppl.) 5: S467-S590.

Maslova NP, Golovneva LB. 2000a. A hamamelid inflorescence with in situ pollen grains from the Cenomanian of eastern Siberia. – Paleontol. J. 34(Suppl.) 1: S40-S49.

Maslova NP, Golovneva LB. 2000b. Lindacarpa gen. nov., a new hamamelid fructification from the Upper Cretaceous of eastern Siberia. – Paleontol. J. 34: 462-468.

Maslova NP, Herman A. 2004. New finds of fossil hamamelids and data on the phylogenetic relationships between the Platanaceae and Hamamelidaceae. – Paleontol. J. 38: 563-575.

Maslova NP, Golovneva LB, Tekleva MV. 2005. Infructescences of Kasicarpa gen. nov. (Hamamelidales) from the Late Cretaceous (Turonian) of the Chulym-Enisey Depression, Western Siberia, Russia. – Acta Palaeobot. 45: 121-137.

Matthew CJ. 1980. Embryological studies in Hamamelidaceae: development of female gametophyte and embryogeny in Hamamelis virginiana. – Phytomorphology 30: 172-180.

Matthiessen A. 1962. A contribution to the embryology of Paeonia. – Acta Horti Berg. 20: 57-61.

Mauritzon J. 1930. Beitrag zur Embryologie der Crassulaceen. – Bot. Not. 1930: 233-250.

Mauritzon J. 1933. Studien über Embryologie der Familien Crassulaceae und Saxifragaceae. – Ph.D. diss, University of Lund, Sweden.

Mayuzumi S, Ohba H. 2004. The phylogenetic position of eastern Asian Sedoideae (Crassulaceae) inferred from chloroplast and nuclear DNA sequences. – Syst. Bot. 29. 587-598.

Meijden R van der, Caspers N. 1971. Haloragaceae. – In: Steenis CGGJ van (ed), Flora Malesiana I, 7, Wolters-Noordhoff, Groningen, pp. 239-263.

Melikian AP. 1973. Seed-coat types of Hamamelidaceae and allied families in relation to their systematics. – Bot. Žurn. 58: 350-359. [In Russian]

Melville R. 1983. The affinity of Paeonia and a second genus of Paeoniaceae. – Kew Bull. 38: 87-105.

Mendes EJ. 1978. 71. Haloragaceae. – In: Launert E (ed), Flora Zambesiaca 4, Flora Zambesiaca Managing Committee, London, pp. 74-81.

Mendes EJ, Vidigal MP. 1978. 70. Hamamelidaceae. – In: Launert E (ed), Flora Zambesiaca 4, Flora Zambesiaca Managing Committee, London, pp. 71-73.

Merxmüller H, Friedrich H-C, Grau J. 1971. Cytotaxonomische Untersuchungen zur Gattungsstruktur von Crassula. – Ann. Naturh. Mus. Wien 75: 111-119.

Mes THM. 1995. Phylogenetic and systematic implications of chloroplast and nuclear spacer sequence variation in the Macaronesian Sempervivoideae and related Sedoideae (Crassulaceae). – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys Publ., Leiden, The Netherlands, pp. 30-44.

Mes THM. 1996. Origin and evolution of the Macaronesian Sempervivoideae (Crassulaceae). – Ph.D. diss., Universeit Utrecht, The Netherlands.

Mes THM, Hart H ‘t. 1994. Sedum surculosum and S. jaccardianum (Crassulaceae) share a unique 70 bp deletion in the chloroplast DNA trnL(UAA)-trnF(GAA) intergenic spacer. – Plant Syst. Evol. 193: 213-221.

Mes THM, Hart H ‘t. 1996. The evolution of growth-forms in the Macaronesian genus Aeonium (Crassulaceae) inferred from chloroplast RFLPs and morphology. – Mol. Ecol. 5: 351-363.

Mes THM, Brederode J van, Hart H ’t. 1996. Origin of the woody Macaronesian Sempervivoideae and the phylogenetic position of the East African species of Aeonium. – Bot. Acta 109: 477-491.

Mes THM, Wiejers GJ, Hart H ‘t. 1997. Phylogenetic relationships in Monanthes (Crassulaceae) based on morphological, chloroplast and nuclear DNA variation. – J. Evol. Biol. 10: 193-216.

Mesler MR, Cole JC, Wilson P. 1991. Natural hybridization in western gooseberries (Ribes subg. Grossularia, Grossulariaceae). – Madroño 38: 115-129.

Messinger W, Liston A, Hummer K. 1993. Restriction site mapping of Ribes nuclear ribosomal DNA. – Acta Hort. 352: 175-184.

Messinger W, Hummer K, Liston A. 1999. Ribes (Grossulariaceae) phylogeny as indicated by restriction-site polymorphisms of PCR-amplified chloroplast DNA. – Plant Syst. Evol. 217: 185-195.

Metcalfe CR. 1952. Medusandra richardsiana Brenan: anatomy of the leaf, stem, and wood. – Kew Bull. 7: 237-244.

Metcalfe CR. 1962. Notes on the systematic anatomy of Whittonia and Peridiscus. – Kew Bull. 15: 472-475.

Meurman O. 1928. Cytological studies in the genus Ribes. – Hereditas 11: 289-356.

Meyrán J, López L. 2003. Las Crasuláceas de México. – Soc. Mexic. Cactol., A.C. México, D.F., pp. 1-234.

Mildbraed J. 1954. Die Schausamen von Paeonia corallina Retz. – Ber. Deutsch. Bot. Ges. 67: 73-74.

Miller JM, Bohm BA. 1979. Flavonoids of Leptarrhena pyrolifolia. – Phytochemistry 18: 1412-1413.

Miller JM, Bohm BA. 1980. Flavonoid variation in some North American Saxifraga species. – Biochem. Syst. Ecol. 8: 279-289.

Miller RB. 1975. Systematic anatomy of the xylem and comments on the relationships of Flacourtiaceae. – J. Arnold Arbor. 56: 20-102.

Mione T, Bogle AL. 1987. Comparative ontogeny of the flowers of Hamamelis virginiana and Loropetalum chinense (Hamamelidaceae). – Amer. J. Bot. 74: 620-621.

Mione T, Bogle AL. 1990. Comparative ontogeny of the inflorescence and flower of Hamamelis virginiana and Loropetalum chinense (Hamamelidaceae). – Amer. J. Bot. 77: 77-91.

Mizushima M. 1968. On the flower of Disanthus cercidifolius Maxim. – J. Jap. Bot. 43: 522-544.

Mohana Rao PR. 1974. Seed anatomy in some Hamamelidaceae and phylogeny. – Phytomorphology 24: 113-139.

Mohana Rao PR. 1986. Seed and fruit anatomy in Cercidiphyllum japonicum with a discussion on the affinities of Cercidiphyllaceae. – Flora 178: 243-249.

Moody ML. 2004. Systematics of the angiosperm family Haloragaceae R. Br. emphasizing the aquatic genus Myriophyllum: phylogeny, hybridization and character evolution. – Ph.D. diss., University of Connecticut, Storrs, Connecticut.

Moody ML, Les DH. 2007. Phylogenetic systematics and character evolution in the angiosperm family Haloragaceae. – Amer. J. Bot. 94: 2005-2025.

Moody ML, Les DH. 2010. Systematics of the aquatic angiosperm genus Myriophyllum (Haloragaceae). – Syst. Bot. 35: 121-139.

Moore DM. 1969. Saxifragodes, a new genus of Saxifragaceae from Tierra del Fuego. – Bot. Not. 122: 322-329.

Moran RV. 1942a. Delimitation of genera and subfamilies in the Crassulaceae. – Desert Plant Life 14: 125-128.

Moran RV. 1942b. The status of Dudleya and Stylophylum. – Desert Plant Life 14: 149-157.

Moran RV. 1949. Graptopetalum bartramii in Chihuahua. – Desert Plant Life 21: 53-56.

Moran RV. 1966. The section Centripetalia of Sedum. – Cact. Succ. J. 38: 75-81.

Moran RV. 1967. Echeveria procera, a new species from Oaxaca, Mexico. – Cact. Succ. J. 39: 182-185.

Moran RV. 1978. Resurrection of Cremnophila. – Cact. Succ. J. 50: 139-146.

Moran RV. 1992. Thompsonella Britton & Rose (Crassulaceae) with T. colliculosa, a new species. – Cact. Succ. J. 64: 37-44.

Moran RV. 1994. The genus Lenophyllum. – Haseltonia 2: 1-19.

Moran RV. 1996. Altamiranoa into Sedum (Crassulaceae). – Haseltonia 4: 46.

Moran RV. 2000. Circumscission in Cotyledon: with thoughts on what is Cotyledon, and on how A. P. de Candolle was right all along and they should have listened. – Cact. Succ. J. 72: 306-308.

Moran RV, Meyrán J. 1974. Tacitus bellus, un nuevo género y especie de Crassulaceae de Chihuahua, México. – Cact. Succ. Mex. 19: 75-84.

Moreau F. 1971. Apport des caractères stomatiques à la taxinomie et à la phylogénie des Saxifragées. – Bull. Soc. Bot. France 118: 381-427.

Moreau F. 1976. Types stomatiques et trichome foliaire des Saxifragoïdées (Saxifragacées). – Rev. Cytol. Biol. Vég. 39: 329-341.

Moreau F. 1984. Contribution phytodermatologique à la systématique des Saxifragacées sensu stricto et des Crassulacées. – Rev. Cytol. Biol. Vég. 7: 31-92.

Morf E. 1950. Vergleichend-morphologische Untersuchungen am Gynoeceum der Saxifragaceen. – Ber. Schweiz. Bot. Ges. 60: 516-590.

Morgan DR, Soltis DE. 1993. Phylogenetic relationships among members of Saxifragaceae sensu lato based on rbcL sequence data. – Ann. Missouri Bot. Gard. 80: 631-660.

Mort ME, Mori SA. 2004. Crassulaceae. – In: Smith N, Mori SA, Henderson A, Stevenson DW, Heald SV (eds), Flowering plants of the Neotropics, Princeton University Press, New York, pp. 118-120.

Mort ME, Soltis DE. 1999. Phylogenetic relationships and the evolution of ovary position in Saxifraga section Micranthes. – Syst. Bot. 24: 139-147.

Mort ME, Soltis DE, Soltis PS, Francisco-Ortega J, Santos-Guerra A. 2001. Phylogenetic relationships and evolution of Crassulaceae inferred from matK sequence data. – Amer. J. Bot. 88: 76-91.

Mort ME, Soltis DE, Soltis PS, Francisco-Ortega J, Santos-Guerra A. 2002. Phylogenetics and evolution of the Macaronesian clade of Crassulaceae inferred from nuclear and chloroplast sequence data. – Syst. Bot. 27: 271-288.

Mort ME, Levsen N, Randle CP, Jaarsveld E van, Palmer A. 2005. Phylogenetics and diversification of Cotyledon (Crassulaceae) inferred from nuclear and chloroplast DNA sequence data. – Amer. J. Bot. 92: 1170-1176.

Mort ME, Soltis DE, Soltis PS, Santos-Guerra A, Francisco-Ortega J. 2007. Physiological evolution and association between physiology and growth form in Aeonium (Crassulaceae). – Taxon 56: 453-464.

Mort ME, Randle CP, Burgoyne P, Smith G, Jaarsveld E, Hopper SD. 2009. Analyses of cpDNA matK sequence data place Tillaea (Crassulaceae) within Crassula. – Plant Syst. Evol. 283: 211-217.

Mort ME, O’Leary TR, Carillo-Reyes P, Nowell T, Archibald JK, Randle CP. 2010. Phylogeny and evolution of Crassulaceae: past, present and future. – Schumannia 6: 69-86.

Moskov IV. 1964. On the development of the embryo in some species of Paeonia L. – Bot. Žurn. 49: 887-894. [In Russian]

Moteetee A, Nagendran CR. 1997. Comparative anatomical studies in five southern African species of Crassula I. Structure of the stem and the root. – South Afr. J. Bot. 63: 90-94.

Mu X-J, Wang F-X. 1985. The early development of embryo and endosperm of Paeonia lactiflora. – Acta Bot. Sin. 87: 7-12. [In Chinese]

Murgai P. 1959. The development of the embryo in Paeonia – a reinvestigation. – Phytomorphology 9: 275-277.

Nagaraj M, Nijalingappa BHM. 1967. Embryological studies in Myriophyllum intermedium DC. – Proc. Indian Acad. Sci., Sect. B, 65: 210-220.

Nagaraj M, Nijalingappa BHM. 1974. Embryological studies in Laurembergia hirsuta. – Bot. Gaz. 135: 19-28.

Nakazawa M, Wakabayashi M, Ono M, Murata J. 1997. Molecular phylogenetic analysis of Chrysosplenium (Saxifragaceae) in Japan. – J. Plant Res. 110: 265-274.

Nelson EA, Sage TL, Sage RF. 2005. Functional leaf anatomy of plants with crassulacean acid metabolism. – Funct. Plant Biol. 32: 409-419.

Nemirovich-Danchenko EN. 1994. Seed structure in Penthorum sedoides and P. chinense (Penthoraceae). – Bot. Žurn. 79: 64-69. [In Russian]

Nicholls KW, Bohm BA. 1984. The flavonoids of Lithophragma (Saxifragaceae). – Can. J. Bot. 62: 1636-1639.

Nicholls KW, Bohm BA, Wells EF. 1986. The flavonoids of Mitella, Bensoniella, and Conimitella (Saxifragaceae). – Can. J. Bot. 64: 525-530.

Niedenzu F. 1891. Hamamelidaceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(2a), W. Engelmann, Leipzig, pp. 115-130.

Nowicke JW, Bittner JL, Skvarla J. 1986. Paeonia: exine substructure and plasma ashing. – In: Blackmore S, Ferguson IK (eds.), Pollen and spores: form and function, Linnean Society, London, pp. 81-95.

Nyffeler R. 1992. A taxonomic revision of the genus Monanthes Haworth (Crassulaceae). – Bradleya 10: 49-82.

Nyffeler R. 1995. Hybridization in Monanthes (Crassulaceae). – In: Hart H ’t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys Publ., Leiden.

Oginuma K, Tobe H. 1991. Karyomorphology and evolution in some Hamamelidaceae and Platanaceae (Hamamelididae: Hamamelidales). – Bot. Mag. (Tokyo) 104: 115-135.

Ohba H. 1977. The taxonomic status of Sedum telephium and its allied species (Crassulaceae). – Bot. Mag. (Tokyo) 90: 41-56.

Ohba H. 1978. Generic and infrageneric classification of the Old World Sedoideae (Crassulaceae). – J. Fac. Sci. Univ. Tokyo, Sect. III, 12: 139-198.

Ohba H. 1989. Biogeography of the genus Rhodiola (Crassulaceae), with special reference to the floristic interaction between the Himalaya and the Arctic Region. – In: Ohba H, Hayami I, Mochizuki K (eds), Current aspects of biogeography in West Pacific and East Asian regions, University of Tokyo, pp. 115-133.

Ohba H. 1995. Systematic problems of Asian Sedoideae. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys, Leiden, pp. 151-158.

Okada H, Tamura M. 1979. Karyomorphology and relationship of the Ranunculaceae. – J. Jap. Bot. 54: 65-77.

Okuyama Y, Kato M, Murakami N. 2004. Pollination by fungus gnats in four species of the genus Mitella (Saxifragaceae). – Bot. J. Linn. Soc. 144: 449-460.

Okuyama Y, Fujii N, Wakabayashi M, Kawakita A, Ito M, Watanabe M, Murakami N, Kato M. 2005. Nonuniform concerted evolution and chloroplast capture: heterogeneity of observed introgression patterns in three molecular data partition phylogenies of Asian Mitella (Saxifragaceae). – Mol. Biol. Evol. 22: 285-296.

Okuyama Y, Pellmyr O, Kato M. 2008. Parallel floral adaptations to pollination by fungus gnats within the genus Mitella (Saxifragaceae). – Mol. Phylogen. Evol. 46: 560-575.

Olfelt JP, Furnier GP, Luby JL. 1998. Reproduction and development of the endangered Sedum integrifolium ssp. leedyi (Crassulaceae). – Amer. J. Bot. 85: 346-351.

Olfelt JP, Furnier GP, Luby JL. 2001. What data determine whether a plant’s taxon is distinct enough to merit legal protection? A case study of Sedum integrifolium (Crassulaceae). – Amer. J. Bot. 88: 401-410.

Oliver D. 1896. Peridiscus lucidus, Benth. – Hooker’s Ic. Pl. IV, 25: pl. 2441.

Orchard AE. 1975. Taxonomic revisions in the family Haloragaceae I. The genera Haloragis, Haloragodendron, Glischrocaryon, Meziella, and Gonocarpus. – Bull. Auckland Inst. Mus. 10: 1-293.

Orchard AE. 1979. Myriophyllum (Haloragaceae) in Australasia 1. New Zealand: a revision of the genus and a synopsis of the family. – Brunonia 2: 247-287.

Orchard AE. 1981. A revision of South American Myriophyllum (Haloragaceae), and its repercussions on some Australian and North American species. – Brunonia 4: 27-65.

Orchard AE. 1985. Myriophyllum (Haloragaceae) in Australasia 2. The Australian species. – Brunonia 8: 173-291.

Orchard AE. 1990. Haloragaceae. – In: George AS (ed), Flora of Australia 18, Australian Government Publ. Service, Canberra, pp. 5-85.

Orchard AE, Keighery GJ. 1993. The status, ecology and relationships of Meziella (Haloragaceae). – Nuytsia 9: 111-117.

Orchard AE, Lepschi BJ, Hislop M. 2005. New taxa, a new record and a rediscovery in Western Australian Haloragis (Haloragaceae). – Nuytsia 15: 431-443.

Ornduff RO. 1969. Ecology, morphology, and systematics of Jepsonia (Saxifragaceae). – Brittonia 21: 286-298.

Ornduff RO. 1971. The reproductive system of Jepsonia heterandra. – Evolution 25: 300-311.

Oskolski A, Kodrul T, Jin J. 2012. Altingioxylon hainanensis sp. nov.: earliest fossil wood record of the family Altingiaceae in Eastern Asia and its implications for historical biogeography. – Plant Syst. Evol. 298: 661-669.

Ozdilek A, Gengel B, Kandemir G, Tayanc Y, Velioglu E, Kaya Z. 2012. Molecular phylogeny of relict-endemic Liquidambar orientalis Mill. based on sequence diversity of the chloroplast-encoded matK gene. – Plant Syst. Evol. 298: 337-349.

Packer JG. 1963. The taxonomy of some North American species of Chrysosplenium L., section Alternifolia Franchet. – Can. J. Bot. 41: 85-103.

Pan JT. 1978. The genus Saxifraga in Qing-Zang Plateau. – Acta Phytotaxon. Sin. 16: 11-35.

Pan K-Y, Yang Q-E. 1994. Karyotypes of Disanthus and Mytilaria (Hamamelidaceae). – Acta Phytotaxon. Sin. 32: 235-239.

Pan K-Y, Lu A-M, Wen J. 1990. Characters of leaf epidermis in Hamamelidaceae (s.l.). – Acta Phytotaxon. Sin. 28: 1-26. [In Chinese with English summary]

Pan K-Y, Lu A-M, Wen J. 1991. A systematic study on the genus Disanthus Maxim. (Hamamelidaceae). – Cathaya 3: 1-28. [In Chinese]

Parnell J. 1991. Pollen morphology of Jovibarba Opiz and Sempervivum L. (Crassulaceae). – Kew Bull. 46: 733-738.

Parra V, Vargas CF, Eguiarte LE. 1993. Reproductive biology, pollen and seed dispersal, and neighborhood size in the hummingbird-pollinated Echeveria gibbiflora (Crassulaceae). – Amer. J. Bot. 80: 153-159.

Parra V, Vargas CF, Eguiarte LE. 1998. Is Echeveria gibbiflora (Crassulaceae) fecundity limited by pollen availability? An experimental study. – Funct. Ecol. 12: 591-595.

Pastre A, Pons A. 1973. Quelques aspects de la systématique des Saxifragacées à la lumière des données de la palynologie. – Pollen Spores 15: 117-133.

Pérez-Calix E. 1998. Sedum mocinianum (Crassulaceae) una especie nueva del centro de México. – Acta Bot. Mex. 45: 49-54.

Petersen OG. 1893. Halorrhagidaceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(7), W. Engelmann, Leipzig, pp. 226-237.

Pigg KB, Ickert-Bond SM, Wen J. 2004. Anatomically preserved Liquidambar (Altingiaceae) from the middle Miocene of Yakima Canyon, Washington State, USA, and its biogeographic implications. – Amer. J. Bot. 91: 499-509.

Pilon-Smits EAH. 1992. Variation and evolution of crassulacean acid metabolism in Sedum and Aeonium (Crassulaceae). – Ph.D. diss., Universiteit Utrecht, The Netherlands.

Pilon-Smits EAH, Hart H ‘t, Maas JW, Meesterburrie JAN, Kreuler R van, Brederode J. 1992. The evolution of Crassulacean Acid Metabolism in Aeonium inferred from carbon isotope composition and enzyme activities. – Oecologia 91: 548-553.

Pino G. 2006. Little-known Crassulaceae of Central Peru. – Haseltonia 12: 55-66.

Pinto P, Ruiz PM (eds). 1984. Haloragaceae. – Instituto de Ciencias Naturales, Bogotá, Colombia.

Plouvier V. 1965. Études chimiotaxinomiques sur les Saxifragacées. – Bull. Soc. Bot. France, Mém., 112: 150-161.

Praeger RL. 1921. An account of the genus Sedum as found in cultivation. – J. Roy. Horticult. Soc. 46: 1-314.

Praeger LR. 1928a. On some doubtful species of the African section of the Sempervivum group. – Proc. Roy. Irish Acad., sect. B, 38: 1-24.

Praeger LR. 1928b. The Canarian Sempervivum-flora: its distribution and origin. – J. Bot. 66: 218-229.

Praeger LR. 1929. Semperviva of the Canary Islands Area. – Proc. Roy. Irish Acad., Sect. B, 38: 454-499.

Praeger RL. 1932. An account of the Sempervivum group. – Royal Horticultural Society, London.

Praglowski J. 1970. The pollen morphology of the Haloragaceae with reference to taxonomy. – Grana 10: 159-239.

Praglowski J. 1974. Pollen morphology of the Trochodendraceae, Tetracentraceae, Cercidiphyllaceae, and Eupteleaceae with reference to taxonomy. – Pollen Spores 16: 449-467.

Prantl K. 1889. Beiträge zur Morphologie und Systematik der Ranunculaceen. – Engl. Bot. Jahrb. Syst. 9: 225-273.

Prantl K. 1891. Trochodendraceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(2), W. Engelmann, Leipzig, pp. 21-23.

Qiu Y-L, Chase MW, Hoot SB, Conti E, Crane PR, Sytsma KJ, Parks CR. 1998. Phylogenetics of the Hamamelidae and their allies: parsimony analyses of nucleotide sequences of the plastid gene rbcL. – Intern. J. Plant Sci. 159: 891-905.

Quimby MW. 1971. The floral morphology of the Crassulaceae. – Ph.D. diss., Cornell University, Ithaca, New York.

Raadts E. 1972. Zwei neue Kalanchoë aus Arabien und Somaliland. – Bot. Jahrb. Syst. 91: 478-482.

Raadts E. 1977. The genus Kalanchoë (Crassulaceae) in tropical East Africa. – Willdenowia 8: 101-157.

Raadts E. 1979. Rasterelektronenmikroskopische und anatomische Untersuchungen an Konnektivdrüsen von Kalanchoe (Crassulaceae). – Willdenowia 9: 169-175.

Raadts E. 1981. Über zwei arabische Kalanchoë-Arten (Crassulaceae). – Willdenowia 11: 327-331.

Raadts E. 1983. Cytotaxonomische Untersuchungen an Kalanchoë (Crassulaceae) 1. Kalanchoë marmorata Baker und 2 neue Kalanchoë-Arten aus Ostafrika. – Willdenowia 13: 373-385.

Raadts E. 1985. Cytotaxonomische Untersuchungen an Kalanchoë (Crassulaceae) 2. Chromosomenzahlen intermediärer Formen. – Willdenowia 15: 157-166.

Raadts E. 1989. Cytotaxonomische Untersuchungen an Kalanchoë (Crassulaceae) 3. Chromosomenzahlen ostafrikanischer Kalanchoë-Sippen. – Willdenowia 19: 169-174.

Raadts E. 1995. Über zwei Kalanchoë-Arten (Crassulaceae) und eine neue Varietät aus dem Jemen. – Willdenowia 25: 253-259.

Rabe AJ, Soltis DE. 1999. Pollen tube growth and self-incompatibility in Heuchera micrantha var. diversifolia (Saxifragaceae). – Intern. J. Plant Sci. 160: 1157-1162.

Radtke MG, Pigg KB, Wehr W. 2005. Fossil Corylopsis and Fothergilla leaves (Hamamelidaceae) from the lower Eocene flora of Republic, Washington, USA, and their evolutionary and biogeographic significance. – Intern. J. Plant Sci. 166: 347-356.

Rakotobe EA. 1996. Le genre endemique malgache Dicoryphe Du Petit-Thouars (Hamamélidacées): repartition et phytogéographie. – Biogéographie de Madagascar: 177-182.

Ramamonjiarisoa BA. 1980. Comparative anatomy and systematics of African and Malagasy woody Saxifragaceae sensu lato. – Ph.D. diss., University of Massachusetts, Amherst, Massachusetts.

Rao PRM. 1974. Seed anatomy in some Hamamelidaceae and phylogeny. – Phytomorphology 24: 113-139.

Rao TA, Bhupal OP. 1974. Typology of foliar sclereids in various taxa of Hamamelidaceae. – Proc. Indian Acad. Sci., Sect. B, 79: 127-138.

Record SJ. 1941. American woods of the family Flacourtiaceae. – Trop. Woods 68: 40-57.

Reinsch A. 1889 [1890]. Über die anatomischen Verhältnisse der Hamamelidaceae mit Rücksicht auf ihre systematische Gruppierung. – Engl. Bot. Jahrb. Syst. 11: 347-395.

Rich SM, Ludwig M, Pedersen O, Colmer TD. 2010. Aquatic adventitious roots of the wetland plant Meionectes brownii can photosynthesize: implications for root function during flooding. – New Phytol. 190: 311-319.

Rieseberg LH, Soltis DE. 1987. Allozyme differentiation between Tolmiea menziesii and Tellima grandiflora (Saxifragaceae). – Syst. Bot. 12: 154-161.

Rocén T. 1928. Beitrag zur Embryologie der Crassulaceen. – Svensk Bot. Tidskr. 22: 368-376.

Rodríguez ACB, Caballero-Ruano A, Parrondo MSJ. 1979. Estudio anatómico-fisiológico del leño de las Crassulaceas en relación con el habitat. – An. Edafol. Agrobiol. 38: 2169-2179.

Rombach S. 1911. Die Entwicklung der Samenknospe bei den Crassulaceen. – Rec. Trav. Bot. Néerl. 8: 189-200.

Ronse De Craene L-P, Roels P, Smets E, Backlund A. 1998. The floral development and floral anatomy of Chrysosplenium alternifolium, an unusual member of the Saxifragaceae. – J. Plant Res. 111: 573-580.

Rosendahl CO. 1914. A revision of the genus Mitella with a discussion of geographical distribution and relationships. – Engl. Bot. Jahrb. Syst. [Suppl.] 50: 375-397.

Rosendahl CO, Butters FK, Lakela O. 1936. A monograph on the genus Heuchera. – Minnesota Studies in Plant Science 2, University of Minnesota Press, Minneapolis, Minnesota, pp. 1-180.

Rosenthal K. 1931. Daphniphyllaceae. – In: Engler A (†), Harms H, Pax F (eds), Die natürlichen Pflanzenfamilien, 2. Aufl., Bd. 19c, W. Engelmann, Leipzig, pp. 233-235.

Rowley JR. 1992. Pollen of Cercidiphyllum (Cercidiphyllaceae). – Bot. Žurn. 77: 1-3.

Rudramuniyappa CK, Annigeri BG. 1984. A histochemical study of meiocytes, microspores, pollen and the tapetum in Kalanchoë. – Nord. J. Bot. 4: 661-667.

Rüffle L. 1980. Wachstums-Modus und Blattmorphologie bei altertümlichen Fagales und Hamamelidales der Kreide und der Gegenwart. – In: 100 Jahre Arboretum Berlin, Akademie-Verlag, Berlin, pp. 329-341.

Rünger W, Wehr B. 1969. Über den Einfluss der Tageslänge und der Temperatur auf die Blütenbildung einiger Echeveria-Arten. – Gartenbauwissenschaft 34: 111-143.

Rylova TB. 1989. Morphological features of pollen in some fossil and extant species of Itea (Iteaceae). – Bot. Žurn. 74: 694-699. [In Russian]

Said C. 1982. Les nectaires floreaux des Crassulacées. Étude morphologique, histologique et anatomique. – Bull. Soc. Bot. France Lett. Bot. 129: 231-240.

Sandwith NY. 1962. Contribution to the flora of tropical America LXIX. A new genus of Peridiscaceae. – Kew Bull. 15: 467-471.

Sang T, Zhang D. 1999. Reconstructing hybrid speciation using sequences of low copy nuclear genes: hybrid origins of five Paeonia species based on Adh gene phylogenies. – Syst. Bot. 24: 148-163.

Sang T, Crawford DJ, Stuessy TF. 1995. Documentation of reticulate evolution in peonies (Paeonia) using internal spacer sequences of nuclear ribosomal DNA: implications for biogeography and concerted evolution. – Proc. Natl. Acad. Sci. U.S.A. 92: 6813-6817.

Sang T, Crawford DJ, Stuessy TF. 1997. Chloroplast DNA phylogeny, reticulate evolution, and biogeography of Paeonia (Paeoniaceae). – Amer. J. Bot. 84: 1120-1136.

Sang T, Donoghue MJ, Zhang D. 1997. Evolution of alcohol dehydrogenase genes in peonies (Paeonia): phylogenetic relationships of putative nonhybrid species. – Mol. Biol. Evol. 14: 994-1007.

Sato Y. 1972. Development of the embryo sac of Daphniphyllum macropodum var. humile (Maxim.) Rosenth. – Sci. Rep. Tohoku Imp. Univ., Ser. IV (Biol.), 36: 129-133.

Savile DBO. 1953. Splash-cup dispersal mechanism in Chrysosplenium and Mitella. – Science 117: 250-251.

Savile DBO. 1954. Taxonomy, phylogeny, host relationship and phytogeography of the microcyclic rusts of Saxifragaceae. – Can. J. Bot. 32: 400-425.

Savile DBO. 1975. Evolution and biogeography of Saxifragaceae with guidance from their rust parasites. – Ann. Missouri Bot. Gard. 62: 354-361.

Savile DBO. 1976. Conimitella (Saxifragaceae) and its rust. – Can. J. Bot. 54: 1977-1978.

Sawada M. 1971. Floral vascularization of Paeonia japonica with some consideration of systematic position of the Paeoniaceae. – Bot. Mag. (Tokyo) 84: 51-60.

Sax K. 1931. Chromosome numbers in the ligneous Saxifragaceae. – J. Arnold Arbor. 12: 198-205.

Saxena NP. 1964. Studies in the family Saxifragaceae I. A contribution to the morphology and embryology of Saxifraga diversifolia Wall. – Proc. Indian Acad. Sci., Sect. B, 60: 38-51.

Scherwin PA, Wilbur RL. 1971. The contributions of floral anatomy to the generic placement of Diamorpha smallii and Sedum pusillum. – J. Elisha Mitchell Sci. Soc. 87: 103-114.

Schindler AK. 1904. Die Abtrenning der Hippuridaceen von den Halorrhagaceen. – Engl. Bot Jahrb. Syst. 34, Beibl. 77: 1-77.

Schoenagel E. 1931. Chromosomenzahl und Phylogenie der Saxifragaceen. – Bot. Jahrb. Syst. 64: 266-308.

Schöffel K. 1932. Untersuchungen über den Blütenbau der Ranunculaceen. – Planta 17: 315-371.

Schönland S. 1891. Crassulaceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(2a), W. Engelmann, Leipzig, pp. 23-38.

Schultheis LM, Donoghue MJ. 2004. Molecular phylogeny and biogeography of Ribes (Grossulariaceae), with an emphasis on gooseberries (subg. Grossularia). – Syst. Bot. 29: 77-96.

Schwaighofer KF. 1908. Ist Zahlbrucknera als eigene Gattung beizubehalten oder wieder mit Saxifraga zu vereinigen? – Sitzungsber. Kaiserl. Akad. Wiss. Math.-Naturwiss. Kl., Wien 117: 25-52.

Segraves KA, Thompson JN. 1999. Plant polyploidy and pollination: floral traits and insect visits to diploid and tetraploid Heuchera grossulariifolia. – Evolution 53: 1114-1121.

Senters AE, Soltis DE. 2003. Phylogenetic relationships in Ribes (Grossulariaceae) inferred from ITS sequence data. – Taxon 52: 51-66.

Shamrov II. 1997. Ovule and seed development in Paeonia lacitiflora (Paeoniaceae). – Bot. Žurn. 82: 24-46. [In Russian]

Shamrov II. 1998. Formirovanie gipostazy, podiuma i postamenta v semyazachatke Nuphar lutea (Nymphaeaceae) i Ribes aureum (Grossulariaceae). – Bot. Žurn. 83: 3-14.

Sharma AK, Gosh S. 1967. Cytotaxonomy of Crassulaceae. – Biol. Zentralbl. Suppl. 86: 313-336.

Shi S, Chang HT, Chen Y, Qu L, Wen J. 1998. Phylogeny of the Hamamelidaceae based on the ITS sequences of nuclear ribosomal DNA. – Biochem. Syst. Ecol. 26: 55-69.

Shi S, Huang Y-L, Zhong Y, Du Y, Zhang Q, Chang H, Boufford DE. 2001. Phylogeny of the Altingiaceae based on cpDNA matK, PY-IGS and nrDNA ITS sequences. – Plant Syst. Evol. 230: 13-24.

Sin J-H, Yoo Y-G, Park K-R. 2002. A palynotaxonomic study of the Korean Crassulaceae. – Korean J. Electron Microscopy 32: 345-360.

Sinnott QP. 1985. A revision of Ribes L. subg. Grossularia (Mill.) Pers. sect. Grossularia (Mill.) Nutt. (Grossulariaceae) in North America. – Rhodora 87: 189-286.

Siplivinsky V. 1983. Sections of the genus Saxifraga L. described by A. Haworth. – Taxon 31: 548-549.

Skvortsova NT. 1960. The structure of epidermis in the members of the family Hamamelidaceae. – Bot. Žurn. 45: 712-717.

Small JK. 1896. Two new genera of Saxifragaceae. – Bull. Torrey Bot. Club 23: 18-20.

Smith H. 1958. Saxifraga of the Himalaya 1. Section Kabschia. – Bull. Brit. Mus. Nat. Hist. (Bot.) 2: 85-129.

Smith H. 1960. Saxifraga of the Himalaya 2. Some new species. – Bull. Brit. Mus. Nat. Hist. (Bot.) 2: 229-265.

Snezhkova SA. 1990. Structure of woods of some representatives of Hydrangeaceae and Grossulariaceae. – Byull. Glav. Bot. Sada 158: 78-80.

Snow R. 1969. Permanent translocation heterozygosity associated with an inversion system in Paeonia brownii. – Heredity 60: 103-106.

Solereder H. 1899. Zur Morphologie und Systematik der Gattung Cercidiphyllum Sieb. et Zucc. mit Berücksichtigung der Gattung Eucommia Oliv. – Ber. Deutsch. Bot. Ges. 17: 387-406.

Soltis DE. 1980a. Karyotypic relationships among species of Boykinia, Heuchera, Mitella, Sullivantia, Tiarella, and Tolmiea (Saxifragaceae). – Syst. Bot. 5: 17-29.

Soltis DE. 1980b. Flavonoids of Sullivantia: taxonomic implications at the genetic level within the Saxifraginae. – Biochem. Syst. Ecol. 8: 149-151.

Soltis DE. 1981. Heterochromatin banding in Boykinia, Heuchera, Mitella, Sullivantia, Tiarella and Tolmiea (Saxifragaceae). – Amer. J. Bot. 69: 108-115.

Soltis DE. 1982. Allozymic variability in Sullivantia (Saxifragaceae). – Syst. Bot. 7: 26-34.

Soltis DE. 1984a. Karyotypic relationships among Elmera, Heuchera, and Tellima (Saxifragaceae). – Syst. Bot. 9: 6-11.

Soltis DE. 1984b. Karyotypes and relationships of species of Jepsonia (Saxifragaceae). – Syst. Bot. 9: 137-141.

Soltis DE. 1984c. Karyotypes of Leptarrhena and Tanakaea (Saxifragaceae). – Can. J. Bot. 62: 671-673.

Soltis DE. 1985. Allozymic differentiation among Heuchera americana, H. parviflora, H. pubescens, and H. villosa (Saxifragaceae). – Syst. Bot. 10: 193-198.

Soltis DE. 1986. Karyotypic relationships among Astilboides, Bergenia, Darmera, and Mukdenia and their implications for subtribal boundaries in Saxifrageae (Saxifragaceae). – Can. J. Bot. 64: 586-588.

Soltis DE. 1987. Karyotypes and relationships among Bolandra, Boykinia, Peltoboykinia, and Suksdorfia (Saxifragaceae: Saxifrageae). – Syst. Bot. 12: 14-20.

Soltis DE. 1988. Karyotypes of Bensoniella, Conimitella, Lithophragma, and Mitella, and relationships in Saxifrageae (Saxifragaceae). – Syst. Bot. 13: 64-72.

Soltis DE. 1991. A revision of Sullivantia (Saxifragaceae). – Brittonia 43: 27-53.

Soltis DE. 2006. Saxifragaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 418-435.

Soltis DE, Bohm BA. 1982. Flavonoids of Penthorum sedoides. – Biochem. Syst. Ecol. 10: 221-224.

Soltis DE, Bohm BA. 1984. Karyology and flavonoid chemistry of the disjunct species of Tiarella (Saxifragaceae). – Syst. Bot. 9: 441-447.

Soltis DE, Bohm BA. 1986. Flavonoid chemistry of diploid and tetraploid cytotypes of Tolmiea menziesii (Saxifragaceae). – Syst. Bot. 11: 20-25.

Soltis DE, Hufford L. 2002. Ovary position diversity in Saxifragaceae: clarifying the homology of epigyny. – Intern. J. Plant Sci. 163: 277-293.

Soltis DE, Kuzoff RK. 1995. Discordance between nuclear and chloroplast phylogenies in the Heuchera group (Saxifragaceae). – Evolution 49: 727-742.

Soltis DE, Soltis PS. 1986. Intergeneric hybridization between Conimitella williamsii and Mitella stauropetala (Saxifragaceae). – Syst. Bot. 11: 293-297.

Soltis DE, Soltis PS. 1993. Molecular data and the dynamic nature of polyploidy. – Crit. Rev. Plant Sci. 12: 243-273.

Soltis DE, Soltis PS. 1997. Phylogenetic relationships in Saxifragaceae sensu lato: a comparison of topologies based on 18S rDNA and rbcL sequences. – Amer. J. Bot. 84: 504-522.

Soltis DE, Soltis PS, Ness BD. 1989. Chloroplast-DNA variation and multiple origins of autopolyploidy in Heuchera micrantha (Saxifragaceae). – Evolution 43: 650-656.

Soltis DE, Soltis PS, Bothel KD. 1990. Chloroplast DNA evidence for the origins of the monotypic Bensoniella and Conimitella (Saxifragaceae). – Syst. Bot. 15: 349-362.

Soltis DE, Soltis PS, Clegg MT, Durbin M. 1990. rbcL sequence divergence and phylogenetic relationships in Saxifragaceae sensu lato. – Proc. Natl. Acad. Sci. U.S.A. 87: 4640-4644.

Soltis DE, Soltis PS, Collier TG, Edgerton ML. 1991. Chloroplast DNA variation within and among genera of the Heuchera group (Saxifragaceae): evidence for chloroplast transfer and paraphyly. – Amer. J. Bot. 78: 1091-1112.

Soltis DE, Mayer MS, Soltis PS, Edgerton M. 1991. Chloroplast-DNA variation in Tellima grandiflora (Saxifragaceae). – Amer. J. Bot. 78: 1379-1390.

Soltis DE, Soltis PS, Thompson JN, Pellmyr O. 1992. Chloroplast DNA variation in Lithophragma (Saxifragaceae). – Syst. Bot. 17: 607-619.

Soltis DE, Morgan DR, Grable A, Soltis PS, Kuzoff R. 1993. Molecular systematics of Saxifragaceae sensu stricto. – Amer. J. Bot. 80: 1056-1081.

Soltis DE, Johnson LA, Looney C. 1996. Discordance between ITS and chloroplast topologies in the Boykinia group (Saxifragaceae). – Syst. Bot. 21: 169-185.

Soltis DE, Kuzoff RK, Conti E, Gornall R, Ferguson K. 1996. matK and rbcL gene sequence data indicate that Saxifraga (Saxifragaceae) is polyphyletic. – Amer. J. Bot. 83: 371-382.

Soltis, DE, Kuzoff RK, Mort ME, Zanis M, Fishbein M, Hufford L, Koontz J, Arroyo MK. 2001. Elucidating deep-level phylogenetic relationships in Saxifragaceae using sequences for six chloroplast and nuclear DNA regions. – Ann. Missouri Bot. Gard. 88: 669-693.

Soltis DE, Tago-Nakazawa M, Xiang Q-Y, Kawano S, Murat J, Wakabayashi M. 2001. Phylogenetic relationships and evolution in Chrysosplenium (Saxifragaceae) based on matK sequence data. – Amer. J. Bot. 88: 883-893.

Soltis DE, Clayton JW, Davis CC, Gitzendanner MA, Cheek M, Savolainen V, Amorim AM, Soltis PS. 2007. Monophyly and relationships of the enigmatic family Peridiscaceae. – Taxon 56: 65-73.

Soltis DE, Mort ME, Latvis M, Mavrodiev EV, O’Meara BC, Soltis PS, Burleigh JG, Casas RR de. 2013. Phylogenetic relationships and character evolution analysis of Saxifragales using a supermatrix approach. – Amer. J. Bot. 100: 916-929.

Soltis PS, Soltis DE. 1986. Anthocyanin content in diploid and tetraploid cytotypes of Tolmiea menziesii (Saxifragaceae). – Syst. Bot. 11: 32-34.

Sopova M. 1971. The cytological study of two Paeonia species from Macedonia. – Fragm. Balc. Mus. Macedon. Sci. Nat. 8: 137-142.

Souèges R. 1936. Les rélations embryogéniques des Crassulacées, Saxifragacées et Hypéricacées. – Bull. Soc. Bot. France 83: 317-329.

Spongberg SA. 1979. Cercidiphyllaceae hardy in temperate North America. – J. Arnold Arbor. 60: 367-376.

Stearn WT. 1946. A study of the genus Paeonia. – The Royal Horticultural Society, London.

Stebbins GL. 1938. Cytogenetic studies in Paeonia II. The cytology of the diploid species and hybrids. – Genetics 23: 83-110.

Stebbins GL. 1939. Notes on some systematic relationships in the genus Paeonia. – Univ. Calif. Publ. Bot. 19: 245-266.

Steen SW, Gielly L, Taberlet P, Brochmann C. 2000. Same parental species, but different taxa: molecular evidence for hybrid origins of the rare endemics Saxifraga opdalensis and S. svalbardensis (Saxifragaceae). – Bot. J. Linn. Soc. 132: 153-164.

Steindl F. 1945. Beitrag zur Pollen- und Embryobildung bei Cynomorium L. – Arch. Julius Klaus-stiftung Vererbungsf. 20, Suppl.: 342-355.

Stephenson R. 1994. Sedum, cultivated stonecrops. – Timber Press, Portland, Oregon.

Stern FC. 1944. Geographical distribution of the genus Paeonia. – Proc. Linn. Soc. London 155: 76-80.

Stern FC. 1946. A study of the genus Paeonia. – The Royal Horticultural Society, London.

Stern WL, Sweitzer EM, Phipps RE. 1970. Comparative anatomy and systematics of woody Saxifragaceae: Ribes. – In: Robson NKB, Cutler DF, Gregory M (eds), New research in plant anatomy, Bot. J. Linn. Soc. 63 [Suppl.], London and New York, pp. 215-237.

Stevens JF. 1995a. The systematic and evolutionary significance of phytochemical variation in the Eurasian Sedoideae and Sempervivoideae (Crassulaceae). – Ph.D. diss., Rijks Universiteit, Groningen, The Netherlands.

Stevens JF. 1995b. Chemotaxonomy of the Eurasian Sedoideae and Sempervivoideae. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys, Leiden, pp. 30-44.

Stevens JF, Hart H ‘t, Hendriks H, Malingré TM. 1992. Alkaloids of some European and Macaronesian Sedoideae and Sempervivoideae (Crassulaceae). – Phytochemistry 31: 3917-3924.

Stevens JF, Hart H ‘t, Hendricks H, Malingré TM. 1993. Alkaloids of the Sedum acre-group (Crassulaceae). – Plant Syst. Evol. 185: 207-217.

Stevens JF, Hart H ‘t, Bolck A, Zwaving JH, Malingré TM. 1994. Epicuticular wax composition of some European Sedum species. – Phytochemistry 35: 389-399.

Stevens JF, Hart H ‘t, Ham RCHJ van, Elema ET, Ent MMVX van den, Wildeboer M, Zwaving JH. 1995. Distribution of alkaloids and tannins in the Crassulaceae. – Biochem. Syst. Ecol. 23: 157-165.

Stevens JF, Hart H ’t, Wollenweber E. 1995. The systematic and evolutionary significance of exudate flavonoids in Aeonium. – Phytochemistry 39: 805-813.

Stevens JF, Hart H ’t, Elema ET, Bolck A. 1996. Flavonoid variation in Eurasian Sedum and Sempervivum. – Phytochemistry 41: 503-512.

Stockey RA, Crane PR. 1983. In situ Cercidiphyllum-like seedlings from the Paleocene of Alberta, Canada. – Amer. J. Bot. 70: 1564-1568.

Stolt KAH. 1928. Die Embryologie von Myriophyllum alterniflorum DC. – Svensk Bot. Tidskr. 22: 305-319.

Stopp K. 1957. Aberrante Dehiszenzformen bei Früchten einiger Crassula-Arten. – Beitr. Biol. Pflanzen 34: 165-175.

Subramanyam K. 1962. Embryology in relation to systematic botany, with particular reference to the Crassulaceae. – In: Plant embryology. A symposium, New Delhi: C.S.I.R., pp. 94-112.

Subramanyam K. 1970. Comparative embryology of angiosperms: Crassulaceae, Campanulaceae, Sphenocleaceae, Pentaphragmataceae, Stylidiaceae. – Bull. Natl. Sci. Acad. India 41: 84-89, 306-312, 313-316, 317-320, 321-324.

Supratman U, Fujita T, Akiyama K, Hayashi H. 2001. Insecticidal compounds from Kalanchoe daigremontiana x tubiflora. – Phytochemistry 58: 311-314.

Sutton DA. 1989. The Daphniphyllaceae: a systematic review. – In: Crane PR, Blackmore S (eds), Evolution, systematics, and fossil history of the Hamamelidae 1: Introduction and ”lower” Hamamelidae, Syst. Assoc. Spec. Vol. 40A, Clarendon Press, Oxford, pp. 285-291.

Swamy BGL, Bailey IW. 1949. The morphology and relationships of Cercidiphyllum. – J. Arnold Arbor. 30: 187-210.

Takahashi A. 1985. Wood anatomical studies of Polycarpicae I. Magnoliales. – Sci. Rep. Osaka Univ. 34: 29-83.

Tamura M. 2006. Paeoniaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 265-269.

Taneyama M, Yoshida S. 1978. Studies on C-glycosides in higher plants I. Occurrence of bergenin in Saxifragaceae. – Bot. Mag. (Tokyo) 91: 109-112.

Tang M-S, Yang Y-P, Sheue C-R. 2009. Comparative morphology of the leaves of Daphniphyllum (Daphniphyllaceae). – Blumea 54: 63-68.

Tang Y. 1943. Systematic anatomy of the woods of the Hamamelidaceae. – Bull. Fan Mem. Inst. Biol., N. S., 1: 8-63.

Tank DC, Sang T. 2001. Phylogenetic utility of the glycerol-3-phosphate acyltransferase gene: evolution and implications in Paeonia (Paeoniaceae). – Mol. Phylogen. Evol. 19: 421-429.

Tattje DHE, Bos R, Bruins AP. 1980. Constituents of essential oil from leaves of Liquidambar styraciflua L. – Planta Medica 38: 79-85.

Taylor RL. 1965. The genus Lithophragma (Saxifragaceae). – Univ. Calif. Publ. Bot. 37: 1-122.

Teeri JA, Overton J. 1981. Chloroplast ultrastructure in two Crassulacean species and an F1 hybrid with differing biomass delta 13C values. – Plant Cell Environm. 4: 427-431.

Teeri JA, Stowe LG, Murawski DA. 1978. The climatology of two succulent plant families: Cactaceae and Crassulaceae. – Can. J. Bot. 56: 1750-1758.

Thiede J. 1995. Quantitative phytogeography, species richness, and evolution of American Crassulaceae. – In: Hart H ‘t, Eggli U (eds), Evolution and systematics of the Crassulaceae, Backhuys, Leiden, pp. 89-123.

Thiede J. 2004. The genus Dudleya Britton & Rose (Crassulaceae): its systematics and biology. – Cact. Succ. J. 76: 4-11.

Thiede J. 2006. Penthoraceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 292-296.

Thiede J, Eggli U. 2006. Crassulaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 83-118.

Thiede J, Hart H ‘t. 1999. Transfer of four Peruvian Altamiranoa species to Sedum (Crassulaceae). – Novon 9: 124-125.

Thouvenin M. 1890. Recherches sur la structure des Saxifragacées. – Ann. Sci. Nat., sér. VII (Bot.), 12: 1-174.

Thulin M. 1993. Crassulaceae. – In: Lock JM (ed), Flora of Somalia, Royal botanic Gardens, Kew, pp. 87-93.

Tiaghi YD. 1970. Comparative embryology of angiosperms: Paeoniaceae. – Bull. Natl. Sci. Acad. India 41: 53-58.

Tieghem P van. 1898. Sur le genre Penthore considéré comme type d’une famille nouvelle, les Penthoracées. – J. Bot. (Morot) 12: 150-154.

Tillson AH. 1940.The floral anatomy of the Kalanchoideae. – Amer. J. Bot. 27: 595-600.

Toelken HR. 1977. A revision of the genus Crassula in southern Africa 1-2. – Contr. Bolus Herb. 8: 1-331, 332-595.

Tong K. 1930. Studien über die Familie der Hamamelidaceae, mit besonderer Berücksichtigung der Systematik und Entwicklungsgeschichte von Corylopsis. – Bull. Dept. Biol., Coll. Sci., Sun Yatsen Univ. 2: 1-72.

Tzanoudakis D. 1977. Cytotaxonomic study of the genus Paeonia in Greece. – Ph.D. diss., Botanical Inst., University of Patras, Greece.

Tzanoudakis D. 1983. Karyotypes of four wild Paeonia species from Greece. – Nord. J. Bot. 3: 307-318.

Uhl CH. 1948. Cytotaxonomic studies in the subfamilies Crassuloideae, Kalanchoideae, and Cotyledonoideae of the Crassulaceae. – Amer. J. Bot. 35: 695-706.

Uhl CH. 1956. The Crassulaceae and cytotaxonomy. – Cact. Succ. J. 48: 225-229.

Uhl CH. 1961a. Some cytotaxonomic problems in the Crassulaceae. – Evolution 15: 375-383.

Uhl CH. 1961b. The chromosomes of the Sempervivoideae (Crassulaceae). – Amer. J. Bot. 48: 114-123.

Uhl CH. 1963. Chromosomes and phylogeny of the Crassulaceae. – Cact. Succ. J. 35: 3-7.

Uhl CH. 1970. Chromosomes of Graptopetalum and Thompsonella (Crassulaceae). – Amer. J. Bot. 57: 1115-1121.

Uhl CH. 1976a. Chromosomes, hybrids and ploidy of Sedum cremnophila and Echeveria linguifolia (Crassulaceae). – Amer. J. Bot. 63: 806-820.

Uhl CH. 1976b. Chromosomes of Mexican Sedum I. Annual and biennial species. – Rhodora 78: 629-640.

Uhl CH. 1976-1992. Chromosomes of Mexican Sedum I-VI. – Rhodora 79: 629-640; 80: 491-512; 82: 377-402; 85: 243-252; 87: 381-423; 94: 362-370.

Uhl CH. 1978. Chromosomes of Mexican Sedum II. Section Pachysedum. – Rhodora 80: 491-512.

Uhl CH. 1980. Chromosomes of Mexican Sedum III. Section Centripetalia, Fruticisedum and other woody species. – Rhodora 82: 377-402.

Uhl CH. 1989. The hybrid origin of Echeveria x Sayulensis. – Cact. Succ. J. 61: 279-284.

Uhl CH. 1992a. Polyploidy, dysploidy, and chromosome pairing in Echeveria (Crassulaceae) and its hybrids. – Amer. J. Bot. 79: 556-566.

Uhl C. 1992b. Chromosomes of Mexican Sedum VI. Section Sedastrum. – Rhodora 94: 362-370.

Uhl CH. 1993-1995. Intergeneric hybrids in the Mexican Crassulaceae I-V. – Cact. Succ. J. 65: 271-273; 66: 74-80, 175-179, 214-217; 67: 144-147.

Uhl CH. 1993. Tacitus and polyploidy. – Haseltonia 1: 29-34.

Uhl CH. 1994-2005. Chromosomes and hybrids of Echeveria (Crassulaceae) I-IX. – Haseltonia 2: 79-88; 3: 25-33; 3: 34-48; 4: 66-88; 5: 21-36; 6: 63-90; 8: 71-82; 9: 121-145; 11: 138-149.

Uhl CH. 1996. Chromosomes and polyploidy in Lenophyllum (Crassulaceae). – Amer. J. Bot. 83: 216-220.

Uhl CH, Moran R. 1972. Chromosomes of Crassulaceae from Japan and South Korea. – Cytologia 37: 59-81.

Uhl CH, Moran R. 1973. The chromosomes of Pachyphytum (Crassulaceae). – Amer. J. Bot. 60: 648-656.

Uhl CH, Moran R. 1999. Chromosomes of Villadia and Altamiranoa (Crassulaceae). – Amer. J. Bot. 86: 387-397.

Umemoto K. 1974. Chemical composition and form of crystalline inorganic components in Japanese saxifragaceous plants. – Yakugaku Zasshi 94: 1627-1633.

Vandeputte E. 1992. Bloemontogenetische observaties en systematische verwantschappen binnen de Saxifragaceae sensu lato. – Thesis, Katholieke Universiteit Leuven, Belgium.

Vargas P. 1991. On the vegetative and floral development in Saxifraga ser. Ceratophyllae and ser. Pentadactylis (Saxifragaceae). – Taxon 40: 41-43.

Vargas P, Morton CM, Jury SL. 1999. Biogeographic patterns in Mediterranean and Macaronesian species of Saxifraga (Saxifragaceae) inferred from phylogenetic analyses of ITS sequences. – Amer. J. Bot. 86: 724-734.

Velajos M, Carrasco MA, Monge C. 1990. Dos Crassulaceae de Ciudad Real (España). – An. Jard. Bot. Madrid 47: 53-58.

Verdcourt B. 1971. Hamamelidaceae. – In: Milne-Redhead E, Polhill RM (eds), Flora of tropical East Africa, Crown Agents for Oversea Governments and Administrations, London, pp. 1-6.

Verdcourt B. 1973a. Haloragaceae. – In: Milne-Redhead E, Polhill RM (eds), Flora of tropical East Africa, Crown Agents for Oversea Governments and Administrations, London, pp. 1-10.

Verdcourt B. 1973. Escalloniaceae. – In: Polhill RM (ed), Flora of tropical East Africa, Crown Agents for Oversea Governments and Administration, London, pp. 1-4.

Verdcourt B. 1983. 64a. Escalloniaceae. – In: Launert E (ed), Flora Zambesiaca 7 (Part 1), Flora Zambesiaca Managing Committee, London, pp. 1-3.

Vink W. 1957. Hamamelidaceae. – In: Steenis CGGJ van (ed), Flora Malesiana I, 5(3), Noordhoff-Kolff N. V., Djakarta, pp. 363-379.

Wadhwa BM. 1983. Two new species of Saxifraga from Burma. – Kew Bull. 38: 487-490.

Wakabayashi M. 1970. On the affinity in Saxifragaceae s. lato with special reference to the pollen morphology. – Acta Phytotaxon. Geobot. 24: 128-145. [In Japanese with English summary]

Wakabayashi M. 1973. On Saxifraga Sect. Diptera of Japan, with description of a new species. – Acta Phytotaxon. Geobot. 25: 154-169.

Wakabayashi M, Ohba H. 1999. Chromosome numbers of seven species of Sedum and Sinocrassula indica (Crassulaceae) in East Himalaya. – J. Jap. Bot. 74: 228-235.

Walters JL. 1952. Heteromorphic chromosome pairs in Paeonia californica. – Amer. J. Bot. 39: 145-151.

Walters JL. 1962. Megasporogenesis and gametophyte selection in Paeonia californica. – Amer. J. Bot. 49: 787-794.

Walther E. 1936. Phylogeny of Echeveria. – Cact. Succ. J. 8: 82-88.

Walther E. 1938. Notes on Crassulaceae. – Cact. Succ. J. 10: 22-24.

Walther E. 1972. Echeveria. – California Academy of Sciences, San Francisco, California.

Wang X-Z. 1992. Palaeopalynological evidence of phylogeny in Hamamelidaceae. – Acta Phytotaxon. Sin. 30: 137-145. [In Chinese with English summary]

Warburg O. 1894. Flacourtiaceae. – In: Engler A, Prantl K (eds), Die natürlichen Pflanzenfamilien III(6a), W. Engelmann, Leipzig, pp. 1-56.

Warming E. 1909. The structure and biology of arctic flowering plants IV. Saxifragaceae 1. Morphology and biology. – Medd. Grønl. 36: 169-236.

Wassmer A. 1955. Vergleichend-morphologische Untersuchungen an den Blüten der Crassulaceen. – Ph.D. diss., Universität Zürich, Switzerland.

Watari S. 1939. Anatomical studies on the leaves of some saxifragaceous plants, with special reference to the vascular system. – J. Fac. Sci. Imp. Univ. Tokyo, Sect. III, Bot. 5: 195-316.

Watari S. 1941. Notes on the crystals in leaves of saxifragaceous plants 1. – Bot. & Zool. (Tokyo) 9: 479-488.

Webb DA, Gornall RJ. 1989a. Saxifrages of Europe with notes on African, American and some Asiatic species. – Christopher Helm, Bromley, London.

Webb DA, Gornall RJ. 1989b. A manual of saxifrages and their cultivation. – Timber Press, Portland, Oregon.

Webb DA, Press JR. 1987. The genus Saxifraga L. in the Madeiran Archipelago. – Bocagiana 105: 1-4.

Weberling F. 1976. Weitere Untersuchungen zur Morphologie des Unterblattes bei den Dikotylen IX. Saxifragaceae s.l., Brunelliaceae, und Bruniaceae. – Beitr. Biol. Pflanzen 52: 163-181.

Weiblen GD, Brehm BG. 1996. Reproductive strategies and barriers to hybridization between Tellima grandiflora and Tolmiea menziesii (Saxifragaceae). – Amer. J. Bot. 83: 910-918.

Weigend M. 2006. Grossulariaceae. – In: Kubitzki K (ed), The families and genera of vascular plants IX. Flowering plants. Eudicots. Berberidopsidales, Buxales, Crossosomatales, Fabales p. p., Geraniales, Gunnerales, Myrtales p. p., Proteales, Saxifragales, Vitales, Zygophyllales, Clusiaceae Alliance, Passifloraceae Alliance, Dilleniaceae, Huaceae, Picramniaceae, Sabiaceae, Springer, Berlin, Heidelberg, New York, pp. 168-176.

Weigend M, Binder M. 2001a. A revision of the genus Ribes (Grossulariaceae) in Bolivia. – Bot. Jahrb. Syst. 123: 111-134.

Weigend M, Binder M. 2001b. Three new species of Ribes L. (Grossulariaceae) from Central and South America. – Syst. Bot. 26: 727-732.

Weigend M, Mohr O, Motley TJ. 2002. Phylogeny and classification of the genus Ribes (Grossulariaceae) based on 5S-NTS sequences and morphological and anatomical data. – Bot. Jahrb. Syst. 124: 163-182.

Weigend M, Gottschling M, Hoot S, Ackerman M. 2004. A preliminary phylogeny of Loasaceae subfam. Loasoideae (Angiospermae: Cornales) based on trn(UAA) sequence data, with consequences for systematics and historical biogeography. – Organisms Divers. Evol. 4: 73-90.

Wells EF. 1984. A revision of the genus Heuchera (Saxifragaceae) in eastern North America. – Syst. Bot. Monogr. 3: 45-121.

Wells EF, Bohm BA. 1980. Chemotaxonomic studies in the Saxifragaceae s.l. 15. The flavonoids of subsection Villosae section Heuchera in the genus Heuchera. – Can. J. Bot. 58: 1459-1463.

Wen J, Shi S. 1999. A phylogenetic and biogeographic study of Hamamelis (Hamamelidaceae), an eastern Asian and eastern North American disjunct genus. – Biochem. Syst. Ecol. 27: 55-66.

Wetzstein HY, Sommer HE. 1982. Leaf anatomy of tissue-cultured Liquidambar styraciflua (Hamamelidaceae) during acclimatization. – Amer. J. Bot. 69: 1579-1586.

Wickens GE. 1987. Crassulaceae. – In: Polhill RM (ed), Flora of tropical East Africa, A. A. Balkema, Rotterdam, pp. 1-66.

Wickens GE. 1982. Studies in the Crassulaceae for the ‘Flora of tropical East Africa’ III. Miscellaneous notes on Crassula, Bryophyllum and Kalanchoe. – Kew Bull. 36: 665-674.

Wickens GE, Bywater M. 1980. Seed studies in Crassula subgen. Disporocarpa. – Kew Bull. 34: 629-637.

Wiggins IL. 1959. Development of the ovule and megagametophyte in Saxifraga hieracifolia. – Amer. J. Bot. 46: 692-697.

Wilkins CK, Bohm BA. 1976. Chemotaxonomic studies in the Saxifragaceae s.l. 4. The flavonoids of Heuchera micrantha var. diversifolia. – Can. J. Bot. 54: 2133-2140.

Wilkinson HP. 1994. Leaf and stem anatomy of the Pterostemonaceae (Engl.) Small: ecological and systematic features. – Bot. J. Linn. Soc. 115: 115-131.

Wilson PG, Moody ML. 2006. Haloragodendron gibsonii (Haloragaceae), a new species from the Blue Mountains, New South Wales. – Telopea 11: 141-146.

Wisniewski M, Bogle AL. 1982. The ontogeny of the inflorescence and flower of Liquidambar styraciflua L. (Hamamelidaceae). – Amer. J. Bot. 69: 1612-1624.

Worsdell WC. 1908. The affinities of Paeonia. – J. Bot. 46: 114-116.

Wu C-Y, Ku T-C. 1992. A new tribe with a new monotypic genus of Saxifragaceae (s.l.) from China. – Acta Phytotaxon. Sin. 30: 193-196. [In Chinese]

Wu W, Zhou R, Huang Y, Boufford DE, Shi S. 2010. Molecular evidence for the natural intergeneric hybridization between Liquidambar and Altingia. – J. Plant Res. 123: 231-239.

Wyatt R, Stoneburger A. 1981. Patterns of ant-mediated pollen dispersal in Diamorpha smallii (Crassulaceae). – Syst. Bot. 6: 1-7.

Xi Y-Z. 1984. The pollen morphology and exine ultrastructure of Paeonia in China. – Acta Bot. Sin. 26: 241-246. [In Chinese]

Xie L, Yi T-S, Li R, Li D-Z, Wen J. 2010. Evolution and biogeographic diversification of the witch-hazel genus (Hamamelis L., Hamamelidaceae) in the northern hemisphere. – Mol. Phylogen. Evol. 56: 675-689.

Xu J-F, Liu C-B, Han A-M, Feng P-S, Su Z-G. 1998. Strategies for the improvement of salidroside production in cell suspension cultures of Rhodiola sachalinensis. – Plant Cell Rep. 17: 288-293.

Yakovlev MS. 1961. Further studies on the new type of embryogenesis in angiosperms. – Bot. Žurn. 46: 1402-1421. [In Russian]

Yakovlev MS, Yoffe MD. 1957. On some peculiar features in the embryogeny of Paeonia L. – Phytomorphology 7: 74-87.

Yamagishi T, Haruna M, Yan X-Z, Chang J-J, Lee K-H. 1989. Antitumor agents, 110. 1,2 bryophyllin B, a novel potent cytotoxic bufadienolide from Bryophyllum pinnatum. – J. Nat. Prod. 52: 1071-1079.

Yan X-L, Ren Y, Tian X-H, Zhang X-H. 2007. Morphogenesis of pistillate flowers of Cercidiphyllum japonicum (Cercidiphyllaceae). – J. Integr. Plant Biol. 49: 1400-1408.

Yen TK. 1936. Floral development and vascular anatomy of the fruit of Ribes aureum. – Bot. Gaz. 98: 105-120.

Yeo PF. 1966. A revision of the genus Bergenia Moench (Saxifragaceae). – Kew Bull. 26: 113-148.

Yoshikawa M, Shimada H, Shimoda H, Murakami N, Yamahara J, Matsuda H. 1996. Bioactive constituents of Chinese natural medicines II. Rhodiolae Radix (1): chemical structures and antiallergic activity of rhodiocyanosides A and B from the underground part of Rhodiola sachalinensis (Pall.) Fisch. et Mey. (Crassulaceae). – Chem. Pharmaceut. Bull. (Tokyo) 44: 2086-2091.

Yu J, Xiao P-G. 1987. A preliminary study of the chemistry and systematics of Paeoniaceae. – Acta Bot. Sin. 25: 172-179. [In Chinese]

Zavada MS, Dilcher DL. 1986. Comparative pollen morphology and its relationship to phylogeny of pollen in the Hamamelidaceae. – Ann. Missouri Bot. Gard. 73: 348-381.

Zhang J-Q, Meng S-Y, Wen J, Rao G-Y. 2014. Phylogenetic relationships and character evolution of Rhodiola (Crassulaceae) based on nuclear ribosomal ITS and plastid trnL-F and psbA-trnH sequences. – Syst. Bot. 39: 441-451.

Zhang J-Q, Meng S-Y, Allen GA, Wen J, Rao G-Y. 2014. Rapid radiation and dispersal out of the Qinghai-Tibetan Plateau of an alpine plant lineage Rhodiola (Crassulaceae). – Molec. Phylogen. Evol. 77: 147-158.

Zhang J-T, Zhang D-W. 1991. Studies on pollen morphology of the genus Corylopsis. – Acta Phytotaxon. Sin. 29: 347-351. [In Chinese]

Zhang Z-Y, Lu A-M. 1989. Phylogenetic relationship of the Daphniphyllaceae. – Acta Phytotaxon. Sin. 27: 17-26. [In Chinese with English summary]

Zhang Z-Y, Lu A-M. 1995. Hamamelidaceae: geographic distribution, fossil history and origin. – Acta Phytotaxon. Sin. 33: 313-339.

Zhao L-C, Li D-Y. 2008. Anatomically preserved seeds of Corylopsis (Hamamelidaceae) from the Miocene of Yunnan, China, and their phytogeographic implications. – Intern. J. Plant Sci. 169: 483-494.

Zhou Z-K, Crepet WL, Nixon KC. 2001. The earliest fossil evidence of the Hamamelidaceae: Late Cretaceous (Turonian) inflorescences and fruits of Altingioideae. – Amer. J. Bot. 88: 753-766.

Zhu W-D, Nie Z-L, Wen J, Sun H. 2013. Molecular phylogeny and biogeography of Astilbe (Saxifragaceae) in Asia and eastern North America. – Bot. J. Linn. Soc. 171: 377-394.

Zielinski QB. 1953. Chromosome numbers and meiotic studies in Ribes. – Bot. Gaz. 114: 265-274.