Euphorbia serpillifolia
Thyme-leafed spurge, Thyme-Leafed Spurge
(c) Trevor Van Loon, some rights reserved (CC BY) · licence
Family: Euphorbiaceae · Type: Herb · Native
Euphorbia serpillifolia (Thyme-leafed spurge) is a native California herb in the Euphorbiaceae family.
Thyme-leafed spurge is a California native annual found in dry, open habitats at low to moderate elevations. Flowering from March to May, this plant produces tiny white petal-like appendages surrounding delicate cyathia clustered at each node. Growing with prostrate to ascending stems that repeatedly fork and spread across the ground, it forms a low, intricate mat reaching 10 to 20 centimeters wide. Its opposite leaves are small and delicate, measuring 3 to 14 millimeters long, with oblong to ovate blades that have finely toothed edges and slightly asymmetric bases. The seeds are small, ovoid, and range from white to brown with subtle surface variations.
Identification and appearance
Key characters: Geographically isolated; insufficient range data provided
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 serpillifolia native to California?
Yes. Euphorbia serpillifolia is native to California (recorded as native).
What plant family does Euphorbia serpillifolia belong to?
Euphorbia serpillifolia is in the Euphorbiaceae family, genus Euphorbia.
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.