Euphorbia eriantha
Beetle spurge
(c) Eric Knight, some rights reserved (CC BY) · licence
Family: Euphorbiaceae · Type: Herb · Native
Euphorbia eriantha (Beetle spurge) is a native California herb in the Euphorbiaceae family, recognized by linear leaves and lobed glands diagnostic.
Beetle spurge is a California native annual found in the southern desert region in rocky canyons and slopes at elevations below 1,000 meters. Flowering from March to April, this plant produces small, clustered cyathia at branch tips with densely puberulent involucres. Growing with erect stems 10 to 50 centimeters tall, the plant has ascending branches that are glabrous or sparsely hairy. Its leaves are linear, 2 to 7 centimeters long, alternately arranged with acute or obtuse tips, and sometimes minutely toothed toward the branch ends. The plant produces small oblong fruits 4 to 5 millimeters long, bearing distinctive 4-angled seeds with tubercled surfaces.
Identification and appearance
Key characters: 18 sympatric species; linear leaves and lobed glands diagnostic
Habitat and range
Habitat: Canyons, rocky slopes
Elevation: < 1000 m
California counties: Riverside, San Bernardino, Imperial, San Diego
Outside California: to Texas, Mexico
Bloom period
Euphorbia eriantha blooms Mar-Apr.
How to tell it apart
vs Croton: Euphorbia bleeds milky white latex and packs its flowers into a tiny cup (cyathium) rimmed with nectar glands; Croton has watery sap, stellate or scaly hairs, and ordinary small separate male and female flowers.; vs Stillingia: Euphorbia flowers sit in a gland-bearing cyathium; Stillingia bears its flowers in a spike with a pair of glands flanking each subtending bract and has no cyathium cup.; vs Ditaxis: Euphorbia has latex and the cyathium; Ditaxis has clear sap, 5-parted petaled male and female flowers, and 2-forked (malpighiaceous) hairs.; vs Asclepias: Both ooze milky sap, but Euphorbia's minute flowers cluster in a cyathium and ripen into a 3-lobed capsule; milkweeds have showy 5-parted flowers with a crown and paired follicles of plumed seeds.; vs Polygonum: Prostrate mat spurges leak milky sap when torn and have paired stipules with opposite leaves at the nodes; knotweeds have clear sap and a papery sheath (ocrea) wrapping each node.
Frequently asked questions
Is Euphorbia eriantha native to California?
Yes. Euphorbia eriantha is native to California (recorded as native).
When does Euphorbia eriantha bloom?
Euphorbia eriantha blooms Mar-Apr.
Where in California does Euphorbia eriantha grow?
Euphorbia eriantha occurs in Riverside, San Bernardino, Imperial, San Diego, at elevations of < 1000 m.
What plant family does Euphorbia eriantha belong to?
Euphorbia eriantha is in the Euphorbiaceae family, genus Euphorbia.
What habitat does Euphorbia eriantha grow in?
Euphorbia eriantha grows in Canyons, rocky slopes.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.