Euphorbia setiloba
Yuma sandmat, Yuma Sandmat
Photo by Chez Brungraber
Family: Euphorbiaceae · Type: Herb · Native
Euphorbia setiloba (Yuma sandmat) is a native California herb in the Euphorbiaceae family, recognized by deeply lobed appendages diagnostic.
Yuma sandmat is a California native annual found in the southern desert bioregion in sandy places at elevations below 1,500 meters. Flowering throughout the year, this plant produces white-and-red cyathia with glands less than half a millimeter long and deeply divided white petal-like appendages. Growing with prostrate, repeatedly forking stems that are two-faced and hairy, the plant spreads in a delicate, intricate pattern. Its opposite leaves are small, two to seven millimeters long, with oblong to ovate blades that have an asymmetric base and acute to rounded tip. The tiny spheric fruits are less than 1.5 millimeters long and bear white to brown seeds with subtle wrinkled surfaces.
Identification and appearance
Key characters: 23 sympatric species; deeply lobed appendages diagnostic
Habitat and range
Habitat: Uncommon. Sandy places
Elevation: < 1500 m
California counties: San Bernardino, Riverside, San Diego, Imperial, Inyo
Outside California: to Texas, Mexico
Bloom period
Euphorbia setiloba blooms All year.
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 setiloba native to California?
Yes. Euphorbia setiloba is native to California (recorded as native).
When does Euphorbia setiloba bloom?
Euphorbia setiloba blooms All year.
Where in California does Euphorbia setiloba grow?
Euphorbia setiloba occurs in San Bernardino, Riverside, San Diego, Imperial, Inyo, at elevations of < 1500 m.
What plant family does Euphorbia setiloba belong to?
Euphorbia setiloba is in the Euphorbiaceae family, genus Euphorbia.
What habitat does Euphorbia setiloba grow in?
Euphorbia setiloba grows in Uncommon. Sandy places.
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.