[Boraginaceae+Vahlia+[Rubiales+[Plantaginales+Solanales]]]


BORAGINACEAE Juss.

de Jussieu, Gen. Plant.: 128. 4 Aug 1789 [’Borragineae’], nom. cons.

Sebestenaceae Vent., Tabl. Règne Vég. 2: 380. 5 Mai 1799 [’Sebestenae’], nom. illeg.; Buglossaceae Hoffmanns. et Link, Fl. Portug. 1: 63. 1 Sep 1809 [’Buglossinae’], nom. illeg.; Hydrophyllaceae R. Br. in Bot. Reg. 3: ad t. 242. 1 Dec 1817 [’Hydrophylleae’], nom. cons.; Anchusaceae Vest, Anleit. Stud. Bot.: 274, 302. 1818 [’Anchusoideae’]; Heliotropiaceae Schrad. in Commentat. Soc. Regiae Sci. Gott. Recent. 4: 192. [Asperifol. Linnaei Comm.: 22.] Dec 1819 [’Heliotropiceae’], nom. cons.; Cerinthaceae Bercht. et J. Presl, Přir. Rostlin: 244. Jan-Apr 1820; Ellisiaceae Bercht. et J. Presl, Přir. Rostlin: 244. 1820 [’Ellisiae’], nom. illeg.; Ellisiales Bercht. et J. Presl, Přir. Rostlin: 244. Jan-Apr 1820 [‘Ellisiae’]; Onosmaceae Martinov, Tekhno-Bot. Slovar: 437. 3 Aug 1820 [’Onosmoides’]; Sagoneaceae Martinov, Tekhno-Bot. Slovar: 557. 3 Aug 1820 [’Sagoneae’]; Boraginales Juss. ex Berchtold et J. Presl, Přir. Rostlin: 244. Jan-Apr 1820 [‘Boragineae’]; Sebestenales Vent. ex Bercht. et J. Presl, Přir. Rostlin: 244. Jan-Apr 1820 [‘Sebestenaceae’], nom. illeg.; Ehretiaceae Mart., Nov. Gen. Sp. Plant. 2: 136, 138. Sep 1827, nom. cons.; Cordiaceae R. Br. ex Dumort., Anal. Fam. Plant.: 20, 25. 1829, nom. cons.; Cordiales R. Br. in C. F. P. von Martius, Consp. Regn. Veg.: 23. Sep-Oct 1835 [‘Cordiaceae’]; Ehretiales Mart. in C. F. P. von Martius, Consp. Regn. Veg.: 22. Sep-Oct 1835 [’Ehretiaceae’]; Echiaceae Raf., Fl. Tellur. 2: 61. Jan-Mar 1837 [’Echidia’]; Cynoglossaceae Döll, Rhein. Fl.: 406. 24-27 Mai 1843 [’Cynoglosseae’]; Echiales Lindl. ex Lindl., Veg. Kingd.: 649. 14-28 Mar 1846; Eutocaceae Horan., Char. Ess. Fam: 124. 30 Jun 1847 [’Polemoniaceae nob. s. Eutocaceae’]; Lennoaceae (Torr.) Solms in Abh. Naturf. Ges. Halle 11: 174. 7 Jan 1870, nom. cons.; Hoplestigmataceae Gilg in Engler et Gilg, Syllabus, ed. 9-10: 322. 6 Nov 1924, nom. cons.; Wellstediaceae (Pilg.) Novák in S. Prát (ed.), Rostlinopis 9: 530. 1943; Hydrophyllales R. Br. in C. F. P. von Martius, Consp. Regn. Veg.: 22. Sep-Oct 1835 [’Hydrophylleae’]; Boraginanae Doweld, Tent. Syst. Plant. Vasc.: xlvii. 23 Dec 2001; Codonaceae M. Weigend et H. H. Hilger in Phytotaxa 10: 27. 28 Oct 2010

Genera/species 120–125/2.400–2.600

Distribution Cosmopolitan except polar areas, with their largest diversity in the Mediterranean, temperate regions in Asia, and in western United States.

Fossils Pollen grains have been found in Oligocene and Miocene layers, and endocarps assigned to Ehretia are known from the Eocene to the Pliocene of Europe. Mericarps (nutlets) of Lithospermum have been described from the Late Miocene of South Dakota.

Habit Usually bisexual (rarely andromonoecious, dioecious or gynodioecious), evergreen trees, shrubs or suffrutices (rarely lianas), perennial, biennial or annual herbs. Many species are xerophytes. Lennoa and Pholisma are achlorophyllous root holoparasites.

Vegetative anatomy Root trichoblasts in radial rows often present. Phellogen ab initio superficial to mid-cortical (sometimes pericyclic). Primary medullary rays narrow or wide. Endodermis often prominent. Primary vascular tissue cylinder, without separate vascular bundles. Secondary lateral growth normal or absent. Vessel elements usually with simple (rarely scalariform, foraminate or reticulate) perforation plates; lateral pits alternate, (simple and/or) bordered pits. Vestured pits sometimes present. Imperforate tracheary xylem elements tracheids (at least in Eriodictyon and Wigandia), fibre tracheids or libriform fibres (sometimes very long) with simple or bordered pits, septate or non-septate (also vasicentric tracheids). Wood rays uniseriate or multiseriate, homocellular or heterocellular. Axial parenchyma apotracheal diffuse or diffuse-in-aggregates, or paratracheal scanty, aliform, lozenge-aliform, winged-aliform, confluent, vasicentric, reticulate, or banded, or absent. Wood elements often storied. Secondary phloem in Cordioideae and Ehretioideae stratified into hard fibrous and soft parenchymatous layers. Sieve tube cells (sieve elements) with nuclear non-dispersive protein bodies; sieve tube plastids S type. Nodes usually 1:1, unilacunar with one leaf trace (sometimes 1:3, unilacunar with three traces, or 3:3, trilacunar with three traces). Secretory cavities absent. Heartwood in some species with gum-like substances. Calciumoxalate as raphides, druses, crystal sand, or single prismatic crystals (sometimes tetrahedral or columnar).

Trichomes Hairs at least in herbaceous species usually bristle- to prickle-like, unicellular or multicellular, simple or branched (sometimes many-armed, dendritic or stellate; rarely arachnoid or lepidote, in Hydrophylloideae), usually with basal cystolith or cystolith-like structure and/or calcified or silicified cell walls; glandular hairs sometimes present (in Lennooideae only uniseriate glandular hairs).

Leaves Usually alternate (spiral; sometimes opposite), usually simple (rarely pinnately or palmately compound), entire or pinnately lobed (rarely palmately lobed; in Lennooideae scale-like, reduced), with conduplicate or ? ptyxis. Stipules and leaf sheath absent. Petiole vascular bundle transection arcuate. Venation usually pinnate (rarely palmate). Stomata anomocytic or anisocytic. Cuticular wax crystalloids? Domatia usually absent (sometimes as pits or hair tufts). Epidermis without mucilaginous idioblasts. Mesophyll often with calciumoxalate as raphides, druses or prismatic crystals. Secretory cavities absent. Leaf margin serrate, crenate or entire.

Inflorescence Usually terminal, scorpioid, paniculate, capitate, spicate or corymbose (flowers rarely solitary; in Lennoa and Pholisma compound spike, thyrse or discoid head). Floral prophylls (bracteoles) usually absent (one sometimes present).

Flowers Usually actinomorphic (sometimes obliquely or vertically zygomorphic). Usually hypogyny (rarely half epigyny). Sepals (four or) five (to ten), usually with imbricate or open (rarely valvate or induplicate-valvate) aestivation, usually persistent, free or more or less connate. Petals (four or) five (to ten), usually with imbricate or contorted (rarely valvate) aestivation, connate often into campanulate or tubular corolla; tube orifice often with corona consisting of tuberous or scale-like corolla appendages. Nectariferous disc annular (non-vascularized) or absent.

Androecium Stamens (four or) five (to ten), as many as petals, usually haplostemonous, antesepalous, alternipetalous. Filaments free, adnate to corolla tube (epipetalous), with or without appendage (in Hydrophylloideae often with basal appendages, sometimes as tubular nectar guides). Anthers usually free (rarely connate into tube), basifixed to dorsifixed, sometimes versatile, tetrasporangiate, introrse, longicidal (dehiscing by longitudinal slits); connective sometimes prolonged; anther placentoid absent. Tapetum secretory, with uninucleate, binucleate or multinucleate cells. Staminodia absent.

Pollen grains Microsporogenesis simultaneous. Pollen grains tricolpate, pentacolpate, hexacolpate, pericolpate, tricolporate, pericolporate, or triporate (rarely dicolpate or polyaperturate; in Lennooideae 3–4[–5]- or 6–8[–10]-aperturate), shed as monads, usually tricellular (rarely bicellular) at dispersal. Sometimes with pseudocolpi alternating with colpi. Exine tectate or semitectate, with columellate infratectum, perforate, reticulate or punctate, verrucate, microgranulate, psilate or scabrate. Pollen grains sometimes dumbbell-shaped. Pollen tube usually with callose plugs (absent in Heliotropioideae, Cordioideae and sometimes in Hydrophylloideae).

Gynoecium Pistil composed of usually two (rarely four to 14) connate median carpels. Ovary usually superior (rarely semi-inferior), finally with usually twice as many locelli (secondary locules) as carpels, due to formation of secondary septa (sometimes incomplete; ovary often distinctly quadrilobate; ovary in Hydrophylloideae sometimes unilocular; rarely with one carpel degenerating and with two locelli or with eight to ten locelli). Style usually single, simple (stylodia sometimes two, free or connate in lower part), gynobasic or terminal. Stigmas one or two, punctate to capitate, usually papillate, usually Dry (sometimes Wet) type. Pistillodium absent. Heterostyly frequent.

Ovules Placentation usually basal to axile (in Hydrophylloideae sometimes parietal [when ovary unilocular]). Ovules usually two (rarely one or more than two) per carpel, usually anatropous (sometimes hemianatropous, campylotropous or amphitropous), ascending to horizontal (rarely pendulous), epitropous, unitegmic, tenuinucellar or weakly crassinucellar. Integument five to c. 20 cell layers thick, rarely vascularized. Placental obturator usually present. Hypostase at least usually present. Endothelium present or absent. Nucellar cap often present. Megagametophyte usually monosporous, Polygonum type (rarely disporous, 8-nucleate, Allium type). Endosperm development usually cellular (sometimes nuclear, rarely seemingly helobial or other aberrant type). Endosperm haustoria micropylar and/or chalazal, or absent. Embryogenesis onagrad, chenopodiad, asterad, or solanad.

Fruit A schizocarp usually with four (rarely two or eight to ten) single-seeded usually nutlike (sometimes drupaceous) mericarps, a loculicidal (rarely also septicidal) capsule (rarely irregularly dehiscent), or a one- to four-seeded drupe, usually with persistent (sometimes also accrescent) calyx.

Seeds Aril absent. Elaiosome present in some species. Seed coat endotestal. Exotesta collapsing. Endotesta persistent. Perisperm not developed. Endosperm copious to sparse, oily or starchy, or absent. Embryo straight or curved, usually well differentiated (in Lennoa and Pholisma spherical and without organs), usually without chlorophyll. Radicula usually upright towards fruit apex. Cotyledons two, usually accumbent. Germination phanerocotylar or cryptocotylar.

Cytology x = (4–)12(–13) (Boraginoideae); x = 5, 9–13, 19 (Hydrophylloideae); x = 5, 7–9, 11–14 etc. (Heliotropioideae); x = 9, 14–16, 19 (Cordioideae); x = 5, 7–11, 13, 16 etc. (Ehretioideae) – Protein bodies (of two very different types) present in nucleus in at least Boraginoideae.

DNA Mitochondrial intron coxII.i3 lost in Borago. Mitochondrial coxI intron present in Ehretia and Heliotropium.

Phytochemistry Flavonols (kaempferol, quercetin), 8-ring-desoxyflavonols, caffeic acid, pyrrolizidine alkaloids as macrocyclic diesters (e.g. as heliosupine), saponins, aliphatic monocarboxylic acids (abundant at least in Boraginoideae and Heliotropioideae), alkannin, prenylated naphthoquinones (making roots red or lilac), terpenoid-derived quinones (Cordioideae), rosmarinic acid, lithospermic acid, hydroxycinnamic acid derivatives (disaccharide esters of rosmarinic acid, lithospermic acid or caffeic acid, e.g. hydroxycinnamic acid depside), and γ-linolenic acid present. Cyanogenic compounds usually absent (tyrosine-derived cyanogenic compounds present at least in Borago). Iridoids, ellagic acid and proanthocyanidins not found. Carbohydrates stored as isokestose and higher inulin oligosaccharides.

Use Ornamental plants, dyeing substances (Alkanna, Buglossoides etc.), honey flowers (Phacelia etc.), timber (especially Cordioideae), fruits, vegetables (Borago), forage plants (Symphytum), medicinal plants.

Systematics The sister-group relationship of Boraginaceae is not clarified. They are members of a polytomy also comprising Vahlia (Vahliaceae) and the clade [Rubiales+[Lamiales+Solanales]]. In some analyses Vahlia is recovered as sister to Boraginaceae (Bremer & al. 2002).

Gynobasic style and schizocarp with four nutlike mericarps have evolved several times in Boraginaceae.

Pteleocarpa lamponga (Miq.) Bakh. ex K. Heyne has sometimes been included in Boraginaceae. It is provisionally included in Rubiales, due to some recent results from sequence analyses.

One possible topology is the following: [Codonoideae+[Boraginoideae+[Hydrophylloideae+ [Heliotropioideae+[Cordioideae+Ehretiodeae]]]]].

Codonoideae Retief et A. E. van Wyk in Bothalia 35(1): 79. Mai 2005

1/2. Codon (2; Namibia, Northern and Western Cape). – Prickly shrublets or suffrutices. Calyx deeply linear ten- to twelve-lobate. Corolla broadly ten- to twelve-lobate, campanulate, with flap-shaped appendages near filament bases. Stamens ten to twelve. Pollen grains without pseudocolpi. Pistil composed of two connate carpels. Style terminal, deeply bilobate. Placentation strongly intrusively parietal. Ovules numerous per carpel. Fruit a loculicidal capsule. Testa reticulate-papillate. Endosperm copious. n = ? – Codon is here placed as sister-group to the remaining Boraginaceae, although the support is not very strong. Alternatively, Codon may be sister to Boraginoideae.

[Boraginoideae+[Hydrophylloideae+ [Heliotropioideae+[Cordioideae+Ehretiodeae]]]]

Boraginoideae Arn., Botany: 122. 9 Mar 1832 [‘Borageae’]

90–95/1.415–1.480. Wellstedioideae Pilg. in Bot. Jahrb. Syst. 46: 558. ante Oct 1912. Wellstedia (5; Ethiopia, Somalia, Namibia, Namaqualand in Northern Cape, Socotra). – CynoglosseaeW. D. J. Koch, Syn. Fl. Germ. Helv.: 496. Jan-Oct 1837. Caccinia (5–6; West and Central Asia), Trichodesma (c 35; tropical and subtropical regions in the Old World); Pardoglossum (6; western Mediterranean), Cynoglossum (50–60; temperate and subtropical regions of both hemispheres), Oncaglossum (1; O. pringlei; central Mexico; in Cynoglossum?), Lindelofia (11; Central Asia, Himalayas), Adelocaryum (3; southern Arabian Peninsula, India), Paracaryum (9 or c 70; the Mediterranean and eastwards to Central Asia), Solenanthus (17; the Mediterranean and eastwards to Central Asia and Afghanistan, central China), Rindera (c 25; the Mediterranean and eastwards to Central Asia), Eritrichium (c 30; temperate regions on the Northern Hemisphere), Amblynotus (2; western Siberia, Central Asia, Mongolia, China; in Eritrichium?), Rochelia (c 20; Europe, temperate Asia), Hackelia (c 45; temperate regions on the Northern Hemisphere, mountain regions in Central and South America), Lappula (c 40; Europe, temperate Asia, few species in North America), Lepechiniella (9; Central Asia; in Lappula?), Trigonotis (c 60; eastern Europe and Central Asia to New Guinea), Microula (c 30; Himalayas, western China), Actinocarya (2; Pakistan, northwestern India, Tibet), Bothriospermum (5; tropical to northeastern Asia), Brachybotrys (1; B. paridiformis; Manchuria, eastern Siberia), Myosotis (c 100; temperate regions on both hemispheres, tropical mountains), Asperugo (1; A. procumbens; Europe), Mertensia (c 45; temperate regions on the Northern Hemisphere southwards to Afghanistan and Mexico, with their highest diversity in North America), Omphalodes (c 30; Europe, temperate Asia, Mexico), Pseudomertensia (8; Iran to Himalayas), Myosotidium (1; M. hortensia; Chatham Islands), Pectocarya (10–15; western North America, northwestern Mexico), Eremocarya (1 – 2; E. micrantha; western United States, northwestern Mexico), Oreocarya (21; western United States, northern Mexico), ‘Cryptantha’ (c 100; western North America; diphyletic), Johnstonella (13; southwestern United States, northwestern Mexico, Chile), ‘Plagiobothrys’ (c 70; western North America, Mexico, western South America, few species in East Asia and Australia; polyphyletic), Amsinckia (c 15; western United States, Chile, western Argentina), Greeneocharis (2; western United States, northwestern Mexico), Harpagonella (1; H. palmeri; southwestern United States, northwestern Mexico). – Echiochileae (H. Riedl) Långström et M. W. Chase in E Långström, Syst. Echiochilon & Ogastemma (Boraginac.), Phylogeny Boraginoideae Paper 2: 5. 2002. Antiphytum (10; Mexico, tropical America), Echiochilon (15; northwestern and eastern Africa and eastwards to the Arabian Peninsula and northwestern India), Ogastemma (1; O. pusillum; the Canary Islands, North Africa). – Boragineae G. Don, Gen. Hist. 4: 307, 309. 1837-8 Apr 1838. Moritzia (5; tropical America), Thaumatocaryon (4; Brazil); Brunnera (3; eastern Mediterranean, western Asia and eastwards to western Siberia), Trachystemon (2; the Mediterranean), Borago (3; Europe, the Mediterranean, temperate Asia), Pulmonaria (19; Europe),‘Anchusa’ (33–35; Europe, the Mediterranean, northern and southern Africa, western Asia; paraphyletic; incl. Cynoglottis?), Cynoglottis (2; southeastern Europe, southwestern Asia; in Anchusa?), Gastrocotyle (1; G. hispida; eastern Mediterranean and eastwards to Central Asia and northwestern India), Pentaglottis (1; P. sempervirens; southwestern Europe), Symphytum (c 35; Europe, the Mediterranean and eastwards to Caucasus), Melanortocarya (1; M. obtusifolia; Bulgaria, eastern Mediterranean), Nonea (c 40; the Mediterranean). – Lithospermeae Dumort., Fl. Belg.: 39. 1827. Podonosma (5–10?; southwestern Asia), Alkanna (25–30; southern Europe, the Mediterranean and eastwards to Iran), Echium (c 60; Europe, Macaronesia, the Mediterranean, northern and southern Africa, western Asia), Lobostemon (28; Northern, Western and Eastern Cape), Onosma (c 150; the Mediterranean, Turkey and eastwards to Himalayas and China), Maharanga (10; eastern Himalayas, southwestern China, Thailand), Arnebia (c 25; the Mediterranean and Caucasus and eastwards to Himalayas, tropical Africa), Moltkia (6; northern Italy to northern Greece, southwestern Asia), Mairetis (1; M. microsperma; the Canary Islands, Morocco), Cerinthe (10; southern Europe, the Mediterranean), Paramoltkia (1; P. doerfleri; the Balkan Peninsula), Halacsya (1; H. sendtneri; western Balkan Peninsula), Neatostema (1; N. apulum; Macaronesia, the Mediterranean and eastwards to Iraq), Cystostemon (16; tropical Africa to southwestern Arabian Peninsula), Lithodora (7; northwestern France and western Mediterranean to Turkey), Lithospermum (c 50; temperate regions on both hemispheres, with their highest diversity in North America and Mexico), Glandora (8; southwestern Europe, western Mediterranean, Morocco), Aegonychon (3; southern Europe, the Mediterranean, temperate Asia), Buglossoides (c 10; Europe, the Mediterranean, temperate Asia), Onosmodium (7; North America), Moltkiopsis (1; M. ciliata; North Africa to Iran). – Vestured pits often present. – Unplaced Boraginoideae Afrotysonia (3; eastern and southern Africa), Ancistrocarya (1; A. japonica; Japan), Anoplocaryum (4–5; Central Asia to Siberia), Antiotrema (1; A. dunnianum; southwestern China), Chionocharis (1; C. hookeri; Himalayas), Choriantha (1; C. popoviana; Iraq), Craniospermum (6; temperate Asia), Cynoglossopsis (2; Ethiopia, Somalia), Dasynotus (1; D. daubenmirei; northern Rocky Mountains in the United States), Decalepidanthus (1; D. sericophyllus; Pakistan), Embadium (3; southern Australia), Gyrocaryum (1; G. oppositifolium; Spain), Ivanjohnstonia (1; I. jaunsariensis; northwestern Himalayas), Lacaitaea (1; L. calycosa; eastern Himalayas),  Lasiocaryum (7; Central Asia, Himalayas), Microcaryum (4; Central Asia to western China), Mimophytum (1; M. omphalodoides; Mexico), Nesocaryum (1; N. stylosum; Juan Fernandez [Desventuradas] Islands), Omphalolappula (1; O. concava; southern Australia), Oxyosmyles (1; O. viscosissima; Argentina), Selkirkia (1; S. berteroi; Juan Fernandez [Desventuradas] Islands), Sinojohnstonia (3; western China), Stenosolenium (1; S. saxatile; Central Asia), Stephanocaryum (2; Central Asia), Suchtelenia (1–3; Caucasus to Central Asia), Thyrocarpus (3; China), Tianschaniella (2; Iran to Central Asia), Trachelanthus (3; Iran to Central Asia), Trigonocaryum (1; T. involucratum; Caucasus), Sauria (1; S. akkolia; Kazakhstan). – Temperate (especially warm-temperate) regions on the Northern Hemisphere, fewer species in subtropical areas, on tropical mountains and in the New Guinean Alps, Australia and New Zealand. Usually perennial or annual herbs (sometimes shrubs, rarely trees). Vestured pits present in at least Lithospermeae. Hairs usually with distinct white base. One (sometimes two) of the floral prophylls absent. Corolla orifice often with appendages (corona) from tube; often changing colour during maturation (pink to blue, yellow over pink to blue, yellow to white, etc.) due to changes in pH of cellular liquid. Anther connective often prolonged. Tapetal cells usually multinucleate (in Cynoglossum clade uninucleate). Pollen grains usually tricolporate (sometimes ≥4-colporate), tricellular at dispersal, sometimes with pseudocolpi. Style gynobasic, usually hollow (rarely bifid). Stigma capitate or punctate. Ovules usually tenuinucellar. Integument seven to twelve cell layers thick. Placental obturator present. Nucellar cap sometimes present. Endothelium absent. Endosperm development cellular or nuclear. Endosperm haustoria absent. Fruit usually a schizocarp with (one to) four nutlike mericarps with sclerenchymatous exocarp (in Wellstedia a capsule). Elaiosomes present in many Boragineae. Testa sometimes vascularized. Exotesta usually with thick and lignified external cell walls (sometimes also other types of thickening, or non-thickened). Endotesta disappearing. Endosperm oily (sometimes starchy) or absent. Haustoria absent. x = (4–)12(–13). Meroterpenoids, pyrrolizidine alkaloids, alkannin, prenylated naphthoquinones, rosmarinic acid (hydroxycinnamic acid depside), and γ-linolenic acid present. Polysaccharides stored as isokestose and higher inulin oligosaccharides (fructans).

Wellstedia may be sister to the remaining Boraginoideae. Western South Africa, Namibia, Ethiopia, Somalia, Socotra. Shrublets or suffrutices. Glands peltate. Flowers arranged in two dense rows along stem. Sepals four. Petals four. Nectary absent. Stamens four. Pollen grains with pseudocolpi. Exine tectate or semitectate, perforate to coarsely reticulate. Pistil composed of two connate carpels. Style terminal. Stigma bilobate, Wet type. Ovule one per carpel, pendulous, epitropous, with distinctive chalazal outgrowth. Fruit a primarily loculicidal capsule, with septa separating also from pericarp walls. Seed coat fringed by downwardly pointing subapical hairs. Endosperm absent. Embryo curved. Cotyledons accumbent. n = ? – Wellstedia, in contrast to the majority of Boraginaceae, does not have a number of veins diverging into corolla lobes; the lobes are three-veined and the tube is eight-veined.

The South American clade [Moritzia+Thaumatocaryon] is sister-group to the Old World Boragineae. The Tertiary fossil Prolithospermum belongs in the Boragineae and is so far the only known indigenous representative of this clade in North America (Weigend & al. 2010).

[Caccinia+Trichodesma] may be sister-group to the remaining Cynoglosseae.

Myosotidium hortensia is most closely related to Omphalodes (Heenan et al. 2010).

[Hydrophylloideae+[Heliotropioideae+[Cordioideae+Ehretioideae]]]

Endothelium present. Endosperm haustoria micropylar and sometimes chalazal. Testa, funicle and placenta with single layer of transfer cells with labyrinthine ingrowths of walls.

Hydrophylloideae Burnett, Outlines Bot.: 1006, 1095, 1105. Feb 1835 [‘Hydrophyllidae’]

16/200–210. Draperia (1; D. systyla; California), Ellisia (1; E. nyctelea; North America), Emmenanthe (1; E. penduliflora; southwestern United States), Eriodictyon (9; southwestern United States, northwestern Mexico), Eucrypta (2; southwestern United States, northern Mexico), Hesperochiron (2; southwestern United States, northwestern Mexico), Hydrophyllum (8; North America, Mexico), Miltitzia (8; western North America), Nama (c 45; southwestern United States, Mexico, tropical America, the Hawaiian Islands), Nemophila (17; western and southeastern North America, northwestern Mexico), Phacelia (c 100; North to South America, with their highest diversity in western United States), Pholistoma (3; southwestern United States, northwestern Mexico), Romanzoffia (5–6; western North America and northwestwards to the Aleutian Islands), Tricardia (1; T. watsonii; southwestern United States), Turricula (1; T. parryi; southwestern United States, northwestern Mexico), Wigandia (3; tropical America). – America, with their highest diversity in arid and semiarid regions in western United States and Mexico. Usually herbs (rarely shrubs). Sieve tube nuclei with acicular protein bodies. Leaves usually alternate (rarely opposite), usually simple (rarely compound). Venation pinnate or palmate. Leaf margin lobed, sinuate or dentate (sometimes entire). Inflorescence scorpioid (helicoid). Bracts and floral prophylls (bracteoles) usually absent. Sepals usually connate (sometimes free). Corolla more open than in Boraginoideae. Nectary usually absent. Stamens usually with small scales on each side of base. Pollen grains colporate or colpate. Mesocolpium coarsely reticulate. Pollen tubes usually with callose (absent in e.g. Phacelia). Ovary in principle unilocular, although often secondarily bilocular (with two locelli), usually superior (rarely semi-inferior). Style terminal, sometimes hollow, often bifid, or absent. Stigma punctate. Placentation parietal. Ovules two to numerous per carpel, sometimes pleurotropous, usually tenuinucellar (in Nameae often crassinucellar). Integument five to ten cell layers thick. Endosperm develoment cellular or nuclear. Endosperm haustoria micropylar and chalazal, or absent. Fruit usually a loculicidal (sometimes also septicidal) capsule (rarely indehiscent). Seeds often ruminate by invaginations of exotestal cell walls. Inner and radial exotestal cell walls thick. Endotestal cells persistent, with internal periclinal walls thick. Endosperm sparse to copious (sometimes with hemicellulose as carbohydrate reserve), with lateral outgrowths. Embryo with or without chlorophyll, sometimes short. x = 5, 9–13, 19. Meroterpenoids and rosmarinic acid (hydroxycinnamic acid depside) present. Alkaloids? Tannins absent. Inulin? – Nameae are sister-group to the remaining Hydrophylloideae, according to e.g. Ferguson (1999).

[Heliotropioideae+[Cordioideae+Ehretioideae]]

Stem oxidizing. Pollen tubes without callose. Endosperm development cellular. Fruit with multilayered lignified endocarp. Transfer cells also present in placenta and funicle.

Heliotropioideae Arn., Botany: 122. 9 Mar 1832 [‘Heliotropieae’]

2/350–400. Mallotonia (1; M. gnaphalodes; Florida, Mexico, the West Indies), Heliotropium (350–400; warm-temperate, subtropical and tropical regions of both hemispheres). – Tropical, subtropical and warm-temperate regions on both hemispheres. Trees, shrubs, lianas or herbs. C4 photosynthesis often present in Heliotropium. Stem often turning red at oxidization. Cambium not storied. Pericyclical sheath usually absent. Vestured pits usually absent. Hairs setose to hispid or prickle-like. Tetrahedral crystal sometimes present. Petals with imbricate aestivateion or with involute margins. Stamens connate at apex via papillae. Anther connective not prolonged. Tapetal cells binucleate. Pollen grains sometimes tetracolporate, sometimes with pseudocolpi. Style usually terminal (sometimes absent). Stigma entirely basi-laterally receptive, discoid, later conical and with sterile apex bifid, or hemispherical, often with hair ring, Wet type. Ovules weakly crassinucellar. Integument often eight cell layers thick. Placental obturator present. Parietal tissue approx. one cell layer thick. Nucellar cap approx. two cell layers thick. Fruit a drupe with four single-seeded pyrenes or a schizocarp with four mericarps. Seed coat exotestal. Endosperm usually absent at maturation. Suspensor long. Embryo straight or curved. Cotyledons large. x = 5, 7–9, 11–14 or more. Pyrrolizidine alkaloids present.

[Cordioideae+Ehretioideae]

Sometimes with an unpleasant smell. Endothelium present. A single layer of transfer cells (cells with labyrinthine wall ingrowths) in testa. Endosperm with micropylar (and sometimes chalazal) haustoria.

Cordioideae Beilschm. in Flora 16(Beibl. 7): 69, 106. 14 Jun 1833 [‘Cordiaceae’, ‘Cordieae’]

2/250–320. Cordia (250–320; tropical and subtropical regions of both hemispheres, with their highest diversity in the Neotropics), Hoplestigma (2; Cameroun, Gabon). – Tropical and subtropical regions on both hemispheres, with their highest diversity in the West Indies and South America. Trees, shrubs or lianas. Bark often fibrous. Cambium storied. Vestured pits sometimes present. Secondary phloem stratified. Nodes usually 3:3, trilacunary with three leaf traces (Cordia). Petiole vascular bundle transection annular (bundles sometimes invaginated; central leaf trace in Cordia often invertedly C-shaped at point of fusion with central stele); petiole with wing bundles (sometimes also cortical bundles). Crystal sand and prismatic or column-shaped crystals present. Leaf margin serrate or entire. Extrafloral nectaries sometimes present on lamina, especially on midvein. Floral prophylls (bracteoles) usually absent. Sepals valvate to open, persistent and sometimes accrescent. Petals usually with contorted (sometimes imbricate) aestivation. Anther connective sometimes prolonged. Pollen grains sometimes triporate; pseudocolpi absent. Exine often spinulate. Style usually twice (sometimes once) divided. Stigmas capitate to punctate. Ovules orthotropous, tenuinucellar. Nucellar cap present (Cordia). Fruit often a drupe, with usually one (rarely two or four) pyrenes, often with accrescent calyx (forming anthocarp). Testa vascularized (Cordia), with three or four layers of transfer cells. Endosperm haustoria absent. Cotyledons folded, toothed. x = 9, 14–16, 19. Terpenoid-derived quinones present. – Coldenia is sister to the other Cordioideae.

Hoplestigma, with two species in Cameroon and Gabon, is close to Cordia in DNA analyses. They are deciduous trees with bisexual flowers. The leaves are spiral, simple, entire, estipulate and with entire margin. The venation is pinnate. Perulate buds are present. The inflorescence is terminal, cymose, almost scorpioid. Bracts and floral prophylls (bracteoles) are absent. The flowers are actinomorphic, large and hypogynous. The three to five sepals have valvate aestivation, and are persistent and connate. The calyx opens irregularly in two to four lobes. The eleven to 14 valvate petals are arranged in two to four irregular whorls and are connate at base into a tube. The petal base has three vascular traces (node 3:3?). The c. 20–35 stamens are arranged in usually three irregular whorls. The filiform filaments are free from each other and adnate to the corolla base (epipetalous). The anthers are dorsifixed (subbasifixed), tetrasporangiate, latrorse, and open with longitudinal slits. Staminodia are absent. The pollen grains in Hoplestigma resemble those of many Ehretioideae. They are are tricolporate, with three pseudocolpi and shed in monads. The exine is tectate, with columellate infratectum, and scabrate. The pistil is composed of two connate carpels. The superior ovary is unilocular. The two stylodia are connate at base, recurved at first and later incurved, and hippocraterimorphic. The stigmas are discoid and U-shaped. The placentation is intrusively parietal, with bilobate placentae. The ovules are four per ovary, anatropous, pendulous, unitegmic and (weakly) crassinucellar. The fruit is four-seeded, drupaceous, with a coriaceous exocarp and persistent calyx. The endosperm is sparse. The embryo is relatively large, straight to somewhat curved and well differentiated. The two cotyledons are expanded. The germination is phanerocotylar. – The polymery in perianth and androecium is obviously secondarily gained.

Ehretioideae Arn., Botany: 122. 9 Mar 1832 [‘Ehretieae’] (incl. Lennooideae (Solms) Craven in Blumea 50: 378. 14 Jul 2005)

10/180–200. Ixorhea (1; I. tschudiana; northern Argentina), Ehretia (50–75; tropical and subtropical regions on both hemispheres), Halgania (18; Australia), Rochefortia (13; Central America, the West Indies, Colombia), Bourreria (c 50; tropical America), Tiquilia (27; arid regions in America southwards to Argentina), Lepidocordia (2; northern tropical South America), Hilsenbergia (18; Africa, Madagascar), Lennoa (1–2; L. madreporoides; central Mexico, Colombia, Venezuela), Pholisma (3; southwestern United States, Mexico). – Tropical and subtropical Africa, Madagascar, southern Asia to New Guinea, Australia, the Solomon Islands, southern United States, Mexico, Central America, the West Indies, northernmost South America. Usually trees or shrubs (rarely herbs; Lennoa and Pholisma achlorophyllous root holoparasites on other Ehretioideae). Bark often fibrous. Cortical vascular bundles present at least in Lennoa and Pholisma. Cambium storied. Vestured pits often present. Leaves in Lennoa and Pholisma scale-like. Petiole vascular bundle transection arcuate. Leaf margin usually serrate (sometimes entire). Inflorescence in Lennoa and Pholisma congested. Sepals (four or) five (to 15), with often valvate aestivation, often accrescent (in Lennoa and Pholisma free). Petals (four or) five (to ten), with imbricate aestivation or inflexed. Nectary absent in Lennoa and Pholisma. Anther connective usually not prolonged. Tapetal cells multinucleate. Pollen grains sometimes triporate; pseudocolpi present in at least Bourreria, Ehretia, Lennoa and Pholisma. Exine semitectate, coarsely reticulate. Pistil in Lennoa and Pholisma composed of five to 16 connate carpels. Style once deeply divided (in Lennoa and Pholisma stout). Stigmas capitate, lobate or elongate. Placentation apical to axile (in Lennoa and Pholisma axile). Ovule sometimes one per carpel, crassinucellar (sometimes weakly). Integument ten to twelve cell layers thick. Placental obturator present. Parietal tissue approx. one cell layer thick. Nucellar cap approx. two cell layers thick. Megasporangial epidermal cells anticlinally elongated. Megagametophyte disporous, 8-nucleate, Allium type. Fruit a drupe, with (one- or) two- (to four-)seeded pyrene, or a schizocarp, often with accrescent calyx (in Lennoa and Pholisma an irregularly schizocarpic circumscissile drupe with persistent calyx and corolla). Endosperm copious, sparse or absent. Suspensor long. Embryo curved (in Lennoa and Pholisma minute, undifferentiated). x = 5, 7–11, 13, 16 or more. Special intron in mitocondrial gene cox1. – Bourreria is sister to the clade [Lepidocordia+Rochefortia]. Lepidocordia has vessels arranged in radial groups, apotracheal axial parenchyma and fibre tracheids with bordered pits. Both Lepidocordia and Rochefortia are dioecious. Halgania is sister to Tiquilia, a genus with dry nutlets. Both are sclerophyllous desert shrubs. Finally, the herbaceous or lignified Tiquilia may be sister to Pholisma and Lennoa. Analyses of rps2 also indicate that Lennoa and Pholisma are nested in Ehretioideae and, hence, they parasitize their nearest relatives.

[Lennoa+Pholisma] was sister-group to Cordioideae and these two clades nested inside Heliotropioideae in the study by Nazaire & Hufford (2012).

Cladogram (simplified) of Boraginaceae based on DNA sequence data (Ferguson 1999). Codon and Boraginoideae form a basal sister-group to all other Boraginaceae, and Cordioideae are successive sister to the remainder.

Cladogram (simplified) of Boraginaceae based on DNA sequence data (Gottschling & al. 2001, 2004, etc.). Codon is sister to the remaining Boraginaceae with relatively weak support. Cordioideae are sister to Ehretioideae and Lennooideae. Lennooideae should be included in Ehretioideae, since Ehretioideae will otherwise be paraphyletic, according to some molecular data.

One of 3.227 most-parsimonious cladograms of Hydrophylloideae based on DNA sequence data (Ferguson 1999).


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