Jepson Herbarium
		University of California, Berkeley

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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]; monoecious or dioecious.
Stem: generally branched [ fleshy or spiny].
Leaf: generally simple, alternate or opposite, generally stipuled, petioled; blade entire, toothed, or palmately lobed.
Inflorescence: terminal or axillary panicle, raceme or spike, or (Chamaesyce, Euphorbia) a compact unit enclosed by an involucre appearing flower-like, terminal or axillary, 1 or in whorled, umbel-like, or cyme-like arrays.
Flower: unisexual, ± radial; sepals generally 3–5, free or fused; petals generally 0; stamens 1–many, free or filaments fused; ovary superior, chambers 1–4, styles free or fused, simple or lobed.
Fruit: generally capsule.
Seed: 1 per chamber; seed scar appendage sometimes present, pad- to dome-like.
218 genera, 6000+ species: ± worldwide especially tropics; some cultivated (Aleurites, tung oil; Euphorbia species; Hevea, rubber; Ricinus). Many species ± highly TOXIC. [Wurdack & Davis 2009 Amer J Bot 96:1551–1570] Eremocarpus moved to Croton. Tetracoccus moved to Picrodendraceae. —Scientific Editor: Bruce G. Baldwin.
Unabridged references: [Webster 1994 Ann Missouri Bot Gard 81:1–144]

Key to Euphorbiaceae

Annual, perennial herb, glabrous or hairy; generally monoecious.
Stem: ascending to erect, generally < 1 m; branches equally forked.
Leaf: cauline, generally alternate, occasionally opposite; stipules 0 or gland-like; generally ± sessile; leaf base symmetrical.
Inflorescence: ± flower-like, generally clustered; clusters whorled in umbel-like, or cyme-like, bracted arrays; involucre generally < 5 mm, ± bell-shaped, bracts 5, fused, glands 4–5, alternating with bracts, appendages generally 0; flowers central.
Staminate flower: 5–many, in 5 clusters around pistillate flower; sepals 0; stamens 1.
Pistillate flower: 1, central, stalked; sepals 0; ovary chambers 3, styles 3, generally fused at base, divided or simple.
Fruit: capsule, round to 3-angled or -lobed in ×-section.
Seed: round or angled in ×-section; surface smooth or sculptured, generally with a knob-like structure at attachment scar.
± 1500 species: warm temperate to tropics, worldwide. (Euphorbus, physician to the King of Mauritania, 1st century) [Wheeler 1936 Bull S Calif Acad Sci 35:127–147] Forms monophyletic group with Chamaesyce, often included in Euphorbia. Euphorbia myrsinites L., Euphorbia rigida L. Bieb. occasionally in gardens but not considered naturalized; Euphorbia serrata L. <Noxious weed> considered extirpated from CA; Euphorbia marginata Pursh occasionally persisting from gardens, but recent records lacking. Euphorbia graminea Jacq. <Noxious weed> an urban weed.

Annual.
Stem: erect, branches ascending, 1.5–5 dm, glabrous or hairy and becoming glabrous.
Leaf: 2–7 cm, short-petioled; blade linear, acute to obtuse and abruptly pointed, entire, sparsely hairy.
Inflorescence: 1 or few clustered at branch tips; involucre 1.5–2 mm, obconic, densely hairy; glands 1–3, ± 1.5 mm, round, cupped, lobes 5–7, curved over gland.
Staminate flower: 23–36.
Pistillate flower: style simple.
Fruit: 4–5 mm, oblong, lobed, hairy.
Seed: 3.5–4 mm, oblong, flattened, 4-angled; surface tubercled.
Canyons, rocky slopes; < 100 m. Sonoran Desert;

Previous taxon: Euphorbia dentata
Next taxon: Euphorbia exstipulata var. exstipulata

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].

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Bioregions in which taxon occurs	Red area (if present) is the part of the bioregion lying between the upper and lower elevation limits of the taxon; 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 have georeferencing or identification issues.
Chart based on elevation range in Manual and elevations and coordinates of CCH records. Data provided by the participants of the Consortium of California Herbaria. Note: About half of the CCH records include both elevation and coordinates.	Map made in collaboration with Scott Loarie. Data provided by the participants of the Consortium of California Herbaria. View all CCH records   CCH collections by month Duplicates counted once; synonyms included. Species do not include records of infraspecific taxa. Blue line denotes Manual flowering time.