|University of California, Berkeley|
|Directory News Site Map Home|
|Jepson eFlora: Taxon page
Key to families | Table of families and genera
Indexes to all accepted names and synonyms:
| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Annual to shrub, tree [vine, cactus-like succulent]; monoecious or dioecious; sap clear or milky. Stem: generally branched [fleshy or spiny]. Leaf: generally simple, alternate to whorled, generally stipuled, sessile or petioled; blade entire, toothed, or lobed. Inflorescence: flowers solitary or in terminal or axillary cymes, racemes, spikes, or panicles, or (in Euphorbia) 1° inflorescence a compact, flower-like cyathium with much-reduced flowers enclosed within an involucre of fused bracts, cyathia terminal or axillary, 1 or in cyme-like arrays. Flower: unisexual, ± radial; sepals 0 or 2–6, free or fused; petals generally 0(5); stamens 1–many, free or filaments fused; ovary superior, chambers (1)3(4), styles free or fused, undivided, forked, or variously lobed. Fruit: generally capsule that splits into mericarps that then dehisce, releasing seeds. Seed: 1 per chamber; knob-like appendage sometimes present at attachment scar.
217 genera, 6000+ species: ± worldwide especially tropics; some cultivated (Aleurites, tung oil; Euphorbia species; Hevea, rubber; Ricinus). Many species ± highly TOXIC, due primarily to latex, especially if eaten or in contact with skin, eyes. [Yang et al. 2012 Taxon 61:764–789] Eremocarpus moved to Croton, Tetracoccus moved to Picrodendraceae for TJM2; Chamaesyce moved to Euphorbia here (key to genera revised by Thomas J. Rosatti). —Scientific Editor: Bruce G. Baldwin.
Key to Euphorbiaceae
Annual to shrub [tree; fleshy, ± cactus-like], glabrous or hairy; sap milky; generally monoecious. Stem: prostrate to erect, generally < 1 m; branches arrayed around main stem(s) in 3-dimensions or 2-ranked, resulting in 2-faced stems with adaxial leaf faces all displayed to top side and abaxial leaf faces to bottom side. Leaf: proximal cauline, alternate or opposite, ± sessile to petioled; distal-most cauline in some species whorled, subtending umbel-like cluster of inflorescence branches, leafy bracts distal to whorled leaves generally opposite (whorled); stipules 0, gland-like, thread-like, or scale-like, free or fused, entire to divided; blade entire or toothed (pinnately lobed), base symmetric or asymmetric. Inflorescence: 1° inflorescence a cyathium, resembling a flower; cyathia 1–many, stalked or sessile, terminal (axillary), in generally leafy-bracted cyme-like arrays; cyathium a compact unit comprising an involucre of 5 fused bracts enclosing 1–many reduced staminate flowers and 1(0) pistillate flower; involucre generally 1–5 mm, bract tips alternate with 1–5 nectary glands (derived from modified stipules of involucral bracts), these transversely crescent-shaped or oblong to ± round, flat to cup-like, entire, toothed, or with 2 horn-like lobes, with or without distal, white to pink or red, flat, petal-like appendages; bractlets within involucre membranous or thread-like, often fringed. Staminate flower: (1–4)5–many, generally in 5 clusters around pistillate flower (this difficult to observe); calyx 0; each staminate flower a single stamen jointed to tip of a thread-like pedicel; pedicel persistent, stamen deciduous after pollen released. Pistillate flower: (0)1, central, stalked; calyx 0; ovary chambers 3, styles 3, free or fused at base, undivided or ± deeply forked. Fruit: stalk generally elongating, generally curved, pushing developing fruit from involucre; capsule ± spheric to ovoid or oblong, in ×-section ± round to 3-lobed or -angled. Seed: ± round or ± 3- or 4-angled (flattened) in ×-section, smooth or sculptured; knob-like appendage at attachment scar present or 0.Key to Euphorbia
± 1750 species: warm and/or dry temperate to tropics worldwide. Euphorbus, physician to the King of Mauritania, 1st century [Horn et al. 2012 Molec Phylogen Evol 63:305–326] Forms monophyletic group with Chamaesyce, included here. Euphorbia serrata L. <Noxious weed> considered extirpated from California; 2003 report that Euphorbia exigua L. is possibly naturalizing as yet unconfirmed; Euphorbia marginata Pursh occasionally persisting from gardens, but recent records lacking. Euphorbia graminea Jacq. <Noxious weed> an urban weed. For fruit, seeds, "in ×-section" indicated only if not lobed or angled.
Unabridged references: [Wheeler 1936 Bull S Calif Acad Sci 35:127–147]
Annual, glabrous. Stem: prostrate, rooting at nodes, repeatedly forking, 2-faced. Leaf: opposite throughout, 2-ranked, subsessile; stipules fused into wide, membranous scale; blade 2–7 mm, ovate to oblong, entire, base asymmetric, tip obtuse. Inflorescence: cyathia 1 per node, involucre 0.5–1.5 mm, obconic; glands 4, < 0.5 mm, transversely oblong, dark red-purple; petal-like appendage as wide as or wider than gland, entire or scalloped, white. Staminate flower: 3–8(10). Pistillate flower: styles forked < 1/10. Fruit: ± 1.5 mm, spheric, lobed, glabrous. Seed: < 1.5 mm, ovoid, 4-angled, smooth, white to brown; knob 0.
Disturbed areas; < 750 m. San Joaquin Valley, Central Coast, s South Coast Ranges, Southwestern California, expected elsewhere; to eastern United States; native to South America. [Chamaesyce serpens (Kunth) Small] May–Sep [Online Interchange]
Previous taxon: Euphorbia schizoloba
Next taxon: Euphorbia serpyllifolia
Citation for the whole project: Jepson Flora Project (eds.) 2013. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on Apr 24 2014
Citation for this treatment: [Author of taxon treatment] 2013. Euphorbia, Revision 1, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=25501, accessed on Apr 24 2014
Copyright © 2013 Regents of the University of California
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.
|Bioregions in which Euphorbia serpens occurs|| Markers link to CCH specimen records. If the markers are obscured, reload the page [or change window size and reload]. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.
READ ABOUT YELLOW FLAGS
|View elevation by latitude chart|| Data provided by the participants of the Consortium of California Herbaria.
View all CCH records
CCH collections by month