Euphorbia 'snowflake' 1 Lund Bot Garden 070515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 'snowflake' 2 Lund Bot Garden 070515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1 road 303 N of Ceres, Western Cape, South Africa 100914 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 10 NW of Dadia, Thracia, Greece 060604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 11b NW of Dadia, Thracia, Greece 060606 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 12b Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 12c Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 13a NW of Shangri-la, Yunnan 110708 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 13b NW of Shangri-la, Yunnan 110708 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 13c NW of Shangri-la, Yunnan 110708 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 14a Limahuli Garden, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 14b Limahuli Garden, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 14c Limahuli Garden, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 14d Limahuli Garden, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15a National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15b National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15c National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15d National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15g National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 16a Maui Nui Botanical Garden, Kaluhui, Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 16b Maui Nui Botanical Garden, Kaluhui, Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 16c Maui Nui Botanical Garden, Kaluhui, Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 17a Kilauea Lighthouse, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 17b Kilauea Lighthouse, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 17c Kilauea Lighthouse, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 17d Kilauea Lighthouse, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 18a De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 18b De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1d Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1e Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1f Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 20 Yzerfontein, Western Cape, South Africa 011015 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 21 road 303 N of Ceres, Western Cape, South Africa 100914 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 22 near the sea, De Hoop, Western Cape, South Africa 011024 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 23 S of Botterkloof, Western Cape, South Africa 011018 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 26a Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 26b Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 27a Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 27b Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 28a Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2a Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2c Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2d Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2e Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2f Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 30a Copenhagen Bot Garden 140129 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 30b Copenhagen Bot Garden 140129 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 30c Copenhagen Bot Garden 140129 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 30d Copenhagen Bot Garden 140129 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 31a Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32b Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32c Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32d Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32e Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32f Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32g Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 33a Eagle Gorge Nat. Park, Georgia 170425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 33b Eagle Gorge Nat. Park, Georgia 170425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 34c Eagle Gorge Nat. Park, Georgia 170425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 35b (cult) Brunnby Sk 170611 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36a the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36b the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36c the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36f the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36g the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 37a near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 37b near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 37c near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 37d near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38a Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38b Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38c Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38d Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38e Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38f Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 38g Mantadia Nat Park, Madagascar 191003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3a Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3b Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3c Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3d Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3e Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3f Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 3g Bolonia, Andalusia SP 120324 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 40a Zombitse-Vohibasia Nat Park, Madagascar 191012 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 40b Zombitse-Vohibasia Nat Park, Madagascar 191012 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 40c Zombitse-Vohibasia Nat Park, Madagascar 191012 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 40d Zombitse-Vohibasia Nat Park, Madagascar 191012 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 40e Zombitse-Vohibasia Nat Park, Madagascar 191012 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 42a Nagykovácsi, Hungary 240504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 42b Nagykovácsi, Hungary 240504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 4a SE of Megali Limni, Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 4c SE of Megali Limni, Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 7b along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 7d along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 7e along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 8 NW of Dadia, Thracia, Greece 060606 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia acanthothamnos 1 3 km W of Paleochóra, Crete 800509 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia acanthothamnos 2 Lastos, Karpathos, Greece 040522 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia acanthothamnos 3 Lastos, Karpathos, Greece 040522 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 1 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 2 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 3 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 4 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff terracina 1 Magaluf, Mallorca 110417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff terracina 2 Magaluf, Mallorca 110417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff terracina 3 Magaluf, Mallorca 110417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 10 Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 3 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 4 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 5 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 6 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 7 Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 9 Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp robbiae 2 Lund Bot Garden 130523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp robbiae 3 Lund Bot Garden 130523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp robbiae 4 Lund Bot Garden 130523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia anacampseros 1 Lund Bot Garden 160520 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia anacampseros 2 Lund Bot Garden 160520 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia anacampseros 3 Lund Bot Garden 160520 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 10 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aphylla 1 Mirador de Balcon, Gran Canaria 080410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aphylla 2 Mirador de Balcon, Gran Canaria 080410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aphylla 3 Mirador de Balcon, Gran Canaria 080410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aphylla 4 Mirador de Balcon, Gran Canaria 080410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 1 Masca, Tenerife 940310 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 10 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 11 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 12 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 14 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 15 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 16 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 17 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 2 Jardín Botanico, Gran Canaria 080417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 3 Jardín Botanico, Gran Canaria 080417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 4 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 5 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 6 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 7 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 8 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 9 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 10 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 3 Teno, Tenerife 090513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 4 Teno, Tenerife 090513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 5 Jardin Botanico, Gran Canaria 070417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 6 Teno, Tenerife 090513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 7 Teno, Tenerife 090513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 8 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 9 Teno, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 1 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 2 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 3 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 5 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 6 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 7 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 8 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 9 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia berthelotii 1 between Chipudes and Fortaleza, Tenerife 060423 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia berthelotii 2 between Chipudes and Fortaleza, Tenerife 060423 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 1 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 2 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 3 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 4 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bravoana La Palmita Bot Garden, La Gomera 060422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia canariensis 1 Puerto de Güimar, Tenerife 940311 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia canariensis 3 Puerto de Güimar, Tenerife 940311 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cap-sainte-mariensis 1 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cap-sainte-mariensis 2 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 1 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 2 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 3 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 4 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 5 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata 6 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia capitulata Bergianska, Stockholm 050531 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 1 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 2 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 3 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 4 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 5 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia caput-medusae 6 Cape of Good Hope, Western Cape, South Africa 100915 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cereiformis 3 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cereiformis 4 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 1 S of Calitzdorp, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 2 S of Calitzdorp, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 3 Rooiberg Pass SE of Ladismith, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 4 Rooiberg Pass SE of Ladismith, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 5 S of Botterkloof, Western Cape, South Africa 011018 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 7 Yzerfontein, Western Cape, South Africa 011015 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 8 Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 9 Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 2 Yzerfontein, Western Cape, South Africa 100908 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 3 Yzerfontein, Western Cape, South Africa 100908 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 4 Yzerfontein, Western Cape, South Africa 100908 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 5 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 6 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf carniolica 1 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf carniolica 3 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf characias 2 Gözükücüklü, Turkey 090410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf characias 3 Gözükücüklü, Turkey 090410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf characias 4 along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf characias 5 along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf decussata 1 Knersvlakte NW of Vanrhynsdorp, Western Cape, South Africa 100909 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf decussata 2 Knersvlakte NW of Vanrhynsdorp, Western Cape, South Africa 100909 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 2 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 3 Bontebok National Park, Swellendam, Western Cape, South Africa 161001 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 3 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf fiherensis 1 Ifaty, Madagascar 191010 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf fiherensis 2 Ifaty, Madagascar 191010 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf fiherensis 3 Ifaty, Madagascar 191010 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf fiherensis 4 near Anakao, Madagascar 191011 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf fiherensis 5 near Anakao, Madagascar 191011 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf herniariifolia 1 near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf herniariifolia 2 near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf herniariifolia 3 near Milea, old road to Grevena, N Greece 180628 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf inaequilatera 1 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf loricata 1 S of Clanwilliam, Western Cape, South Africa 100912 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf loricata 2 S of Clanwilliam, Western Cape, South Africa 100912 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 1 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 2 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 3 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 4 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 5 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 6 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf obtusifolia 1 Teno, Tenerife 060413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf obtusifolia 2 Teno, Tenerife 060413 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf officinarum 1 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf officinarum 2 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf officinarum 3 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf officinarum, Euphorbia regis-jubae 1 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf officinarum, Euphorbia regis-jubae 2 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf pithyusa 1 Bocquer valley, Mallorca 110420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf pithyusa 2 Bocquer valley, Mallorca 110420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf pithyusa 3 Bocquer valley, Mallorca 110420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf pithyusa 5 Bocquer valley, Mallorca 110420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf terracina 2 Los Silos, Tenerife 160409 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf terracina 3 Los Silos, Tenerife 160409 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf terracina 4 Los Silos, Tenerife 160409 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf terracina 5 Los Silos, Tenerife 160409 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf viguieri 1 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf viguieri 2 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf viguieri 3 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 1 NE of Spili, Crete 110327 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 4 El Torcal de Antequera, Andulusia SP 120323 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 6 Loarre Castle, N Spain 180526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 7 Loarre Castle, N Spain 180526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 2 Bergianska 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 3 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 4 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 5 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 6 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 7 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 8 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 2 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia coccinea 2 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia coccinea 3 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia coccinea 4 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 1 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 2 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 3 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 4 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 5 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 6 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cyparissias 7 Lyngsjö Sk 140601 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 1 Pereli, Crete 110327 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 2 Pereli, Crete 110327 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 3 Pereli, Crete 110327 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 5 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 6 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 7 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 4 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 5 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dentata 6 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 1 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 2 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 3 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 4 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 5 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 6 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia epithymoides 1 Lund Bot Garden 080505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia epithymoides 2 Lund Bot Garden 080505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia epithymoides 3 Nagykovácsi, Hungary 240504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia epithymoides 4 Nagykovácsi, Hungary 240504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 4 Lund Sk 120702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 5 Lund Sk 120702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 6 Lund Sk 120702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 7 Lund Sk 120702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 11 Hoces del Rio Duratón near Sepúlveda SP 140504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 12 Hoces del Rio Duratón near Sepúlveda SP 140504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 2 Muskmyr, Sundre, Gotland 910728 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 3 Tofta, Gotland 070802 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 6 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 7 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 9 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia falcata between Volada and Othos, Karpathos, Greece 040519 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 2 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 3 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 4 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fragifera 1 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fragifera 2 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fragifera 3 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fruticosa 2 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fruticosa 3 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glauca 2 Otari Botanical Garden, Wellington NZ 151114 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia grandicornis 1 Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia grandicornis 2 Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia grandicornis 3 Copenhagen Bot Garden 121205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia griffithii 1 Lund Bot Garden 070515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hamata 1 Goegap Succulent Garden, Northern Cape, South Africa 100911 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hamata 2 Goegap Succulent Garden, Northern Cape, South Africa 100911 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hamata 3 Goegap Succulent Garden, Northern Cape, South Africa 100911 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hedyotoides 1 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hedyotoides 2 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hedyotoides 3 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hedyotoides 4 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 1 Ojén, Andalusien SP 120319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 2 Ojén, Andalusien SP 120319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 3 Ojén, Andalusien SP 120319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 4 Lund Sk 140402 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 5 Lund Sk 140402 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 6 Videholm, Stora Hammar Sk 130608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 7 Videholm, Stora Hammar Sk 130608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia helioscopia 8 Videholm, Stora Hammar Sk 130608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 1 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 2 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 3 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 4 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 6 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hirsuta 3 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hirsuta 4 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia horrida 2 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia horrida 3 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 1 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 10 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 13 Garinish Island, West Cork, Ireland 170524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 14 Garinish Island, West Cork, Ireland 170524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 2 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 3 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 4 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 5 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 6 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 8 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 9 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hypericifolia 1 National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hypericifolia 2 National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hypericifolia 3 National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hypericifolia 4 National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia illirica 1 Látrány south of Lake Balaton, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia illirica 2 Látrány south of Lake Balaton, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia illirica 3 Látrány south of Lake Balaton, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia illirica 4 Látrány south of Lake Balaton, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia illirica 5 Látrány south of Lake Balaton, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ingens 2 (cult) Tenerife 080406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia invenusta 1 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia invenusta 2 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia invenusta 3 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia invenusta 4 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia jolkinii 1 Shangri-la, Yunnan 110712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia jolkinii 2 Shangri-la, Yunnan 110712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia jolkinii 3 Shangri-la, Yunnan 110712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia jolkinii 4 Shangri-la, Yunnan 110712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lagascae 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lagascae 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lagascae 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp broussonetii 1 Miradór de San Pedro, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp broussonetii 2 Miradór de San Pedro, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp broussonetii 3 Miradór de San Pedro, Tenerife 160404 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp broussonetii 4 Ermita del Buen Paso, La Gomera 060423 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp lamarckii 1 Tamaima, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp lamarckii 2 Tamaima, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp lamarckii 3 Tamaima, Tenerife 160406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp lamarckii 5 Puertito de Güimar, Tenerife 970320 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 1 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 2 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 3 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 4 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 5 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 6 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lambii 7 Chorros de Epina, La Gomera 060420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia larica 1 Masafi Wadi, United Arab Emirates 161101 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia larica 3 Masafi Wadi, United Arab Emirates 161101 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia larica 4 Masafi Wadi, United Arab Emirates 161101 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 10 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 11 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 12 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 13 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 14 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 15 Ballyvaughan, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 2 Copenhagen Bot Garden 130611 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 4 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 5 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 6 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 7 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 9 Copenhagen Bot Garden 130611 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lomelii 1 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lomelii 2 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia longifolia 1 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia longifolia 2 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia longifolia 4 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 2 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 3 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 4 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 5 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 1 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 11 Hovedbangården, Copenhagen DK 101013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 2 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 3 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 4 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 5 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 7 Hovedbangården, Copenhagen DK 101013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 8 Hovedbangården, Copenhagen DK 101013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 9 Hovedbangården, Copenhagen DK 101013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 1 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 3 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 4 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 5 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 6 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 7 Copenhagen Bot Garden 130516 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 8 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 9 Copenhagen Bot Garden 130516 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 1 Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 3 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 4 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 5 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 6 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 7 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 8 the waterfall, Nieuwoudtville, Western Cape, South Africa 100910 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 1 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 2 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 3 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 4 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 5 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 6 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 7 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia medicaginea 8 Copenhagen Bot Garden 140719 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 1 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 2 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 4 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 6 Chinobre, Anaga, Tenerife 160407 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 7 Chinobre, Anaga, Tenerife 160407 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 8 Chinobre, Anaga, Tenerife 160407 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 9 Chinobre, Anaga, Tenerife 160407 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia meloformis 1 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia meloformis 2 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia meloformis 3 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia milii (cult) La Gomera 060424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia milloti 1 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia milloti 2 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia milloti 3 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 1 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 10 Santa Barbara Botanic Garden, CA 130411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 11 Santa Barbara Botanic Garden, CA 130411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 2 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 3 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 4 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 5 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 6 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 7 Santa Barbara Botanic Garden, CA 130411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia misera 8 Santa Barbara Botanic Garden, CA 130411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia multiformis Puu Kaua, Oahu, Hawaii 840226 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 1 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 10 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 11 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 12 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 13 (cult) Stångby Sk 210518 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 14 (cult) Stångby Sk 210518 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 16 (cult) Stångby Sk 210518 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 2 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 3 Copenhagen Bot Garden 140424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 4 Lund Bot Garden 100527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 5 Lund Bot Garden 100527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 6 DBV's Garden, Visby, Gotland 110508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 7 DBV's Garden, Visby, Gotland 110508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 8 DBV's Garden, Visby, Gotland 110508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 9 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia neococcinea 4 Copenhagen Bot Garden 120926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia obesa 1 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia obesa 2 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia obesa 3 Lund Bot Garden 150425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 1 Stora Brunneby, Stenåsa, Öland 120603 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 2 Stora Brunneby, Stenåsa, Öland 120603 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 4 Line myr, Gotland 940621 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 5 Lund Bot Garden 100608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 6 Lund Bot Garden 100608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 7 Kvinnsgröta, Gräsgård, Öland 150606 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 8 Gräsgård, Öland 150604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 9 Gräsgård, Öland 150604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 1 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 10 near Doolin, Clare, Ireland 170527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 11 near Doolin, Clare, Ireland 170527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 12 near Doolin, Clare, Ireland 170527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 13 near Doolin, Clare, Ireland 170527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 3 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 4 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 5 Eleas, Lesvos, Greece 130507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 6 Eleas, Lesvos, Greece 130507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 7 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 8 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 9 near Doolin, Clare, Ireland 170527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias near the sea, De Hoop, Western Cape, South Africa 011024 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplis 1 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplis 3 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 1 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 2 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 3 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 4 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 5 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplus 6 Höllviken Sk 110820 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pillansii 1 Bergianska 061013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pillansii 2 Bergianska 061013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pilosa 3 Göteborg Bot Garden 130524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pilosa 4 Göteborg Bot Garden 130524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pithyusa 3 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pithyusa 4 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia platyphyllos 4 Kaposvár in the Zselic area, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia polygona 2 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia portulacoides 1 Cerro de la Cruz, Zapallar, Chile 171105 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia portulacoides 2 Cerro de la Cruz, Zapallar, Chile 171105 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia portulacoides 3 Cerro de la Cruz, Zapallar, Chile 171105 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia portulacoides 4 Cerro de la Cruz, Zapallar, Chile 171105 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 1 Lund Sk 121020 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 2 Lund Sk 121020 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 3 Lund Sk 121020 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 6 near Lake Mikri Prespa, N Greece 180629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 7 near Lake Mikri Prespa, N Greece 180629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 8 near Lake Mikri Prespa, N Greece 180629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 9 near Lake Mikri Prespa, N Greece 180629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pseudocactus 3 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pterococca 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pterococca 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pterococca 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pterococca 4 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pubescens 1 S of Agiasos, Lesvos, Greece 100513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pubescens 2 S of Agiasos, Lesvos, Greece 100513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pubescens 3 S of Agiasos, Lesvos, Greece 100513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pubescens 4 S of Agiasos, Lesvos, Greece 100513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 1 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 10 Puertito de Güimar, Tenerife 970320 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 2 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 3 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 4 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 5 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 6 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 7 S of Agadir, Morocco 140220 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 9 Ermita del Buen Paso, La Gomera 060423 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia rigida 3 Sicily 190419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia rigida Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 1 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 2 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 3 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 4 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 6 Copenhagen Bot Garden 140129 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 7 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 5 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 6 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 3 Sierras de Tejeda, Almijara y Alhama Natural Park, Andalucía Spain 220417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 4 Sierras de Tejeda, Almijara y Alhama Natural Park, Andalucía Spain 220417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia seguieriana 2 Mt Falakron, N Greece 180703 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia seguieriana 3 Mt Falakron, N Greece 180703 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia seguieriana 4 Mt Falakron, N Greece 180703 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia seguieriana 5 Mt Falakron, N Greece 180703 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 1 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 3 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 6 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 9 Mirador de San Antón, Andalucía Spain 220412 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia squamigera 1 Gibraltar GB 120321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia squamigera 2 Gibraltar GB 120321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia squamigera 3 Gibraltar GB 120321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia squamigera 4 Gibraltar GB 120321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia squamigera 5 Gibraltar GB 120321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stellispina 1 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stellispina 2 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stellispina 3 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 1 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 2 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 3 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 4 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 5 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 6 La Mira near Ifaty, Madagascar 191009 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 7 near Anakao, Madagascar 191011 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stenoclada 8 near Anakao, Madagascar 191011 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stolonifera 2 Rooiberg Pass SE of Ladismith, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stracheyi 1 Baimashan, Yunnan 110710 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stracheyi 2 Baimashan, Yunnan 110710 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 1 Marais de Montfort (Marais de Crolles) FR 150705 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 10 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 11 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 12 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 13 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 14 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 15 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 16 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 18 Paranesti, N Greece 180702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 19 Paranesti, N Greece 180702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 2 Marais de Montfort (Marais de Crolles) FR 150705 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 3 Marais de Montfort (Marais de Crolles) FR 150705 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 8 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 9 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 1 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 4 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 5 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 6 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 7 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 8 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 4 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 3 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 4 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 5 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 6 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 7 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 8 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina var retusa 1 Venta de Yesos, Sorbas gypsum karst, Andalucía Spain 220415 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia tuberosa 1 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia tuberosa 2 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia valida 1 Bergianska 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia valida 2 Bergianska 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia valida 3 Bergianska 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia venenata 1 Kirstenbosch 100906 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia venenata 2 Kirstenbosch 100906 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia verrucosa 1 above Metsovon, Greece 180627 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia verrucosa 2 above Metsovon, Greece 180627 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia viguieri 1 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia virgata 1 W of Kraslava, Latvia 060709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia wallichii 1 near Lijiang, Yunnan 110707 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia wallichii 2 near Lijiang, Yunnan 110707 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 11a NW of Dadia, Thracia, Greece 060606 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 12a Copenhagen Bot Garden 080513 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 14e Limahuli Garden, Kauai, Hawaii 130712 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15e National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15f National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 15h National Tropical Botanical Gardens, Kalehua, Kauaii, Hawaii 130711 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 16d Maui Nui Botanical Garden, Kaluhui, Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 16e Maui Nui Botanical Garden, Kaluhui, Maui, Hawaii 130718 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 18c De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 19a Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 19b Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 19c Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 19d Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1a Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1b Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1c Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 1g Bulgarska Polyana, Bulgaria 120507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 24 S of Botterkloof, Western Cape, South Africa 011018 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 25 Bontebok Nature Reserve, Western Cape, South Africa 011025 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 28b Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 29a Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 29b Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 29c Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 29d Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 29e Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 2b Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 32a Vashlovani Nat. Park, Georgia 170424 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 34a Eagle Gorge Nat. Park, Georgia 170425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 34b Eagle Gorge Nat. Park, Georgia 170425 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 35a (cult) Brunnby Sk 170611 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36d the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 36e the Vedi valley, Armenia 180511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 39a near Anakao, Madagascar 191011 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 4b SE of Megali Limni, Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 5a SE of Megali Limni, Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 5b SE of Megali Limni, Lesvos, Greece 100515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 6 NW of Alanya, Turkey 090406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 7a along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 7c along the river NE of Gazi Pasa, Turkey 090408 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia 9 NW of Dadia, Thracia, Greece 060606 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 5 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 6 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia aff eriantha 7 NW of Ocotillo, CA 130422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 1 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 2 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp amygdaloides 8 Trigrad gorge-Jagodinska, Teshel, Bulgaria 120508 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp robbiae 1 Lund Bot Garden 130523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia amygdaloides ssp robbiae 5 Lund Bot Garden 130523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 1 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 2 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 3 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 4 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 5 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 6 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 7 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 8 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia antisyphilitica 9 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia atropurpurea 13 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 1 N of Barrio de San Andrés, Tenerife 940312 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia balsamifera 2 Teno, Tenerife 970317 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia barrelieri 4 Copenhagen Bot Garden 150421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 5 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia bourgeana 6 Lund Bot Garden 131205 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia canariensis 2 Puerto de Güimar, Tenerife 940311 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cap-sainte-mariensis 3 Copenhagen Bot Garden 100421 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cereiformis 1 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cereiformis 2 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmanii 6 Bontebok Nature Reserve, Western Cape, South Africa 011025 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf burmannii 1 Yzerfontein, Western Cape, South Africa 100908 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf carniolica 2 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf carniolica 4 Garda de Sus, Romania 090615 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf characias 1 Gözükücüklü, Turkey 090410 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf decussata 3 Knersvlakte NW of Vanrhynsdorp, Western Cape, South Africa 100909 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf decussata 4 Knersvlakte NW of Vanrhynsdorp, Western Cape, South Africa 100909 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 1 Bontebok National Park, Swellendam, Western Cape, South Africa 161001 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 1 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf erythrina 2 Bontebok National Park, Swellendam, Western Cape, South Africa 161001 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf inaequilatera 2 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf loricata 3 S of Clanwilliam, Western Cape, South Africa 100912 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf misera 7 Joshua Tree National Park, CA 130416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf pithyusa 4 Bocquer valley, Mallorca 110420 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf seguieriana 1 between Mikroderio and Metaxades, Thracia, Greece 060608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf seguieriana 2 between Mikroderio and Metaxades, Thracia, Greece 060608 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf terracina 1 Los Silos, Tenerife 160409 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf venenata 1 Kirstenbosch 100906 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf venenata 2 Kirstenbosch 100906 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia cf venenata 3 Kirstenbosch 100906 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 2 El Torcal de Antequera, Andulusia SP 120323 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 3 El Torcal de Antequera, Andulusia SP 120323 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp characias 5 Loarre Castle, N Spain 180526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia characias ssp wulfenii 1 Bergianska 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 1 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 3 Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 4 Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 5 Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia clandestina 6 Ladismith, Western Cape, South Africa 100924 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia coccinea 1 Copenhagen Bot Garden 160713 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dendroides 4 Plakias, Crete 110329 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 7 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 8 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia dulcis 9 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 1 E of Veseli, Czekia 950630 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 2 Lund Sk 080523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia esula 3 Lund Sk 120702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 1 Vallkärra, Skåne 920816 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 10 Hoces del Rio Duratón near Sepúlveda SP 140504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 4 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 5 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia exigua 8 Dalby Västermark Sk 130618 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 1 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 5 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp flavicoma 6 Monardilla, Sierra Bermeja, Andalucía Spain 220416 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp verrucosa 1 Moneval NE of Grenoble FR 150705 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia flavicoma ssp verrucosa 2 Moneval NE of Grenoble FR 150705 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia fruticosa 1 Copenhagen Bot Garden 160504 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glareosa 1 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glareosa 2 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glareosa 3 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glareosa 4 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glareosa 5 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia glauca 1 Otari Botanical Garden, Wellington NZ 151114 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia griffithii 2 Lund Bot Garden 070515 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hallii S of Botterkloof, Western Cape, South Africa 011018 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 5 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia heptagona 7 Minwater SW of Oudtshoorn, Western Cape, South Africa 161004 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hirsuta 1 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hirsuta 2 Copenhagen Bot Garden 130604 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia horrida 1 Bergianska 150527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia horrida Bergianska, Stockholm 070221 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 11 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 12 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia hyberna 7 Glengariff Woods, West Cork, Ireland 170523 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ingens 1 (cult) Tenerife 080406 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ingens 1 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lagascae 4 Copenhagen Bot Garden 150812 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lamarckii ssp lamarckii 4 Chio, Tenerife 940309 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia larica 2 Masafi Wadi, United Arab Emirates 161101 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 1 Copenhagen Bot Garden 130611 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lathyris 8 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lomelii 3 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lomelii 4 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lomelii 5 Desert Botanical Garden, Phoenix, Arizona 130426 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia longifolia 3 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia longifolia 5 Pista de Los Lomos, La Palma 090505 (Richard Åkesson) - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 1 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia lophogona 6 Lund Bot Garden 150304 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 10 Hovedbangården, Copenhagen DK 101013 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia maculata 6 Skanör Sk 130901 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia margalidiana 2 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mauritanica 2 Nieuwoudtville, Western Cape, South Africa 011017 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 3 Chinobre, Anaga, Tenerife 9780319 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia mellifera 5 Pista de Los Lomos, La Palma 090505 - Photo: Richard Åkesson (© 2014 Jan Thomas Johansson).

Euphorbia misera 9 Santa Barbara Botanic Garden, CA 130411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 15 (cult) Stångby Sk 210518 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia myrsinites 17 (cult) Stångby Sk 210518 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia neococcinea 1 Copenhagen Bot Garden 120926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia neococcinea 2 Copenhagen Bot Garden 120926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia neococcinea 3 Copenhagen Bot Garden 120926 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia obtusifolia Barranco de Las Cuevas Negras, Tenerife 970321 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia palustris 3 Line myr, Gotland 940621 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 14 Fanore beach, Clare, Ireland 170529 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia paralias 2 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia peplis 2 Kampos, Lesvos, Greece 100512 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pilosa 1 Göteborg Bot Garden 130524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pilosa 2 Göteborg Bot Garden 130524 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pithyusa 1 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pithyusa 2 Jardín Botanico, Soller, Mallorca 110419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia platyphyllos 1 Kaposvár in the Zselic area, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia platyphyllos 2 Kaposvár in the Zselic area, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia platyphyllos 3 Kaposvár in the Zselic area, Hungary 240507 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia polygona 1 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 4 Lund Sk 121020 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia prostrata 5 Lund Sk 121020 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pseudocactus 1 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pseudocactus 2 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia pubiglans 1 Little Karoo Desert National Bot Garden, Worcester, Western Cape, South Africa 161005 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia regis-jubae 8 Chio, Tenerife 940309 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia rigida 1 Sicily 190419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia rigida 2 Sicily 190419 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia ritchiei 5 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 1 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 2 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 3 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis 4 Miradór de Don Martín, Güímar, Tenerife 160405 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 1 Sierras de Tejeda, Almijara y Alhama Natural Park, Andalucía Spain 220417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 10 Sierra de Alcaparaín, Andalucía Spain 220411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 11 Sierra de Alcaparaín, Andalucía Spain 220411 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia segetalis ssp pinea 2 Sierras de Tejeda, Almijara y Alhama Natural Park, Andalucía Spain 220417 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia seguieriana 1 Mt Falakron, N Greece 180703 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 2 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 4 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 5 Magaluf, Mallorca 110422 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 7 Mirador de San Antón, Andalucía Spain 220412 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia serrata 8 Mirador de San Antón, Andalucía Spain 220412 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stolonifera 1 Rooiberg Pass SE of Ladismith, Western Cape, South Africa 161003 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 17 Paranesti, N Greece 180702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 20 Paranesti, N Greece 180702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 4 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 5 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 6 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia stricta 7 Rydebäck S of Helsingborg Sk 170806 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 2 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 3 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia sultan-hassei 9 Imbros, Crete 110328 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 5 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 6 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia taurinensis 7 N of Polygyros, Greece 050526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 1 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina 2 Copenhagen Bot Garden 130821 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina var retusa 2 Venta de Yesos, Sorbas gypsum karst, Andalucía Spain 220415 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina var retusa 3 Venta de Yesos, Sorbas gypsum karst, Andalucía Spain 220415 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia terracina var retusa 4 Venta de Yesos, Sorbas gypsum karst, Andalucía Spain 220415 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia tuberosa 3 De Hoop, Western Cape, South Africa 100921 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia vermiculata 1 Bergianska, Stockholm 050913 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia vermiculata 2 Bergianska, Stockholm 050913 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia viguieri 2 Copenhagen Bot Garden 140625 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia virgata 2 W of Kraslava, Latvia 060709 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Euphorbia virgata 3 Belsőbáránd, Hungary 240505 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).