Spergularia atrosperma
Black seed sand-spurrey
Family: Caryophyllaceae · Type: Herb · Native
Spergularia atrosperma (Black seed sand-spurrey) is a native California herb in the Caryophyllaceae family, recognized by black seeds.
Black seed sand-spurrey is a delicate California native annual found in the Great Valley, Peninsular Ranges, and Mojave Desert regions in alkaline areas, mud flats, and sandy streambeds at elevations below 1,500 meters. Flowering during summer, this plant produces white to rosy flowers with delicate petals in simple or compound inflorescences. Growing with extremely slender stems less than one millimeter in diameter, it forms a fragile, low-growing plant. Its fleshy leaves have small, inconspicuous white to tan stipules with acute tips. The fruit produces distinctive shiny black seeds with a worm-like surface texture, each approximately 0.6 to 0.8 millimeters long.
Identification and appearance
Key characters: 7 sympatric species; black seeds are diagnostic
Habitat and range
Habitat: Uncommon. Alkaline areas, mud flats, streambeds, sandy areas
Elevation: < 1500 m
Outside California: Nevada
Bloom period
Spergularia atrosperma blooms Summer.
How to tell it apart
vs Spergula: Spergularia has simple opposite leaves at nodes; Spergula has whorl-like clusters of 16-30 leaves per node.; vs Erodium: Spergularia has tiny pink/white flowers with round capsules; Erodium has purple flowers with long-beaked stork's-bill fruits.; vs Sabulina: Spergularia has fleshy leaves and triangular stipules; Sabulina has thread-like leaves without stipules.; vs Cakile: Spergularia has opposite fleshy leaves with pink flowers; Cakile has alternate fleshy leaves with 4-petaled mustard flowers.; vs Calandrinia: Spergularia has 5 tiny petals and triangular stipules; Calandrinia has 3-7 showy petals and no stipules.
Frequently asked questions
Is Spergularia atrosperma native to California?
Yes. Spergularia atrosperma is native to California (recorded as native).
When does Spergularia atrosperma bloom?
Spergularia atrosperma blooms Summer.
What plant family does Spergularia atrosperma belong to?
Spergularia atrosperma is in the Caryophyllaceae family, genus Spergularia.
What habitat does Spergularia atrosperma grow in?
Spergularia atrosperma grows in Uncommon. Alkaline areas, mud flats, streambeds, sandy areas.
Related species
Other California species in the same genus, family, or bioregion.
- Spergularia bocconi — Boccone's sand-spurrey
- Spergularia canadensis var. occidentalis — Western sand-spurrey
- Spergularia macrotheca — Sticky sand-spurrey
- Spergularia macrotheca var. leucantha — Sticky sandspurry
- Spergularia macrotheca var. longistyla — Long styled sand spurrey
- Spergularia macrotheca var. macrotheca — Sand spurrey
Sources: Jepson eFlora · 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.