Acmispon prostratus
Nuttall's acmispon, Nuttall's acmispon, Nuttall's acmispon
no rights reserved · CC0
Family: Fabaceae · Type: Herb · Native
Conservation status: CNPS 1B.1
Acmispon prostratus (Nuttall's acmispon) is a native California herb in the Fabaceae family, recognized by extreme coastal habitat and long peduncles.
Nuttall's acmispon is a rare (CNPS 1B.1) California native perennial found in southern coastal California in western San Diego County on beaches, coastal scrub, and disturbed areas at elevations below 30 meters. Flowering from March to June, this plant produces yellow flowers often marked with red, 5 to 7 millimeters long, in compact clusters of 3 to 8 blooms. Growing with prostrate or ascending stems 10 to 100 centimeters long, it spreads in low, sprawling formations. Its leaves are irregularly pinnate with 3 to 6 oblanceolate to obovate leaflets, each 4 to 10 millimeters long. The fruit is an unusual linear curved pod 1 to 1.5 centimeters long, occasionally featuring small horn-like processes and a hooked 2 to 3 millimeter beak.
Identification and appearance
Key characters: 18 sympatric species; distinguished by extreme coastal habitat and long peduncles
Habitat and range
Habitat: Beaches, coastal scrub, disturbed areas
Elevation: < 30 m
California counties: San Diego
Outside California: Baja California
Bloom period
Acmispon prostratus blooms Mar-Jun.
Conservation status
CNPS 1B.1
How to tell it apart
vs Lotus: Same genus - Lotus is an older name for Acmispon, now considered synonymous.; vs Ottleya: Acmispon has yellow pea-shaped flowers in umbels; Ottleya (a buckwheat relative) has tiny white/pink flowers without pea shape.; vs Eriogonum: Acmispon has compound leaves with 3 leaflets; buckwheats (Eriogonum) have simple leaves.; vs Genista: Acmispon leaves are compound with 3 leaflets; Genista (broom) has simple or very small trifoliate leaves on ridged green stems.; vs Hosackia: Acmispon has tiny gland-like stipules; Hosackia has conspicuous papery or leaf-like stipules at leaf bases.
Frequently asked questions
Is Acmispon prostratus native to California?
Yes. Acmispon prostratus is native to California (recorded as native).
When does Acmispon prostratus bloom?
Acmispon prostratus blooms Mar-Jun.
Where in California does Acmispon prostratus grow?
Acmispon prostratus occurs in San Diego, at elevations of < 30 m.
What plant family does Acmispon prostratus belong to?
Acmispon prostratus is in the Fabaceae family, genus Acmispon.
Is Acmispon prostratus rare or endangered?
Acmispon prostratus carries California Rare Plant Rank 1B.1, state rank S1.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.