Tetrapteron palmeri
Palmer's evening primrose
Photo by Chez Brungraber
Family: Onagraceae · Type: Herb · Native
Tetrapteron palmeri (Palmer's evening primrose) is a native California herb in the Onagraceae family, recognized by key differences in stem morphology, habitat, and elevation.
Palmer's evening primrose is a California native annual found in southern Gabilan Range, Santa Clara River Valley, western Transverse Ranges including Tejon Pass, peninsular ranges near Jacumba, western and Inyo Mountains, and eastern Mojave Desert in desert flats and sagebrush scrub at elevations of 600 to 1,400 meters. Flowering from April to May, this plant produces pale yellow to white flowers with petals roughly equal to the anthers. Growing with stems up to 20 millimeters tall that are distinctively swollen and peeling, it has a delicate, compact form. Its leaves range from 15 to 55 millimeters long with fine, minute serrations along the edges. The fruit is a distinctive 4-angled, 4-winged structure 5 to 7 millimeters long, which becomes leathery and slowly splits open when mature.
Identification and appearance
Key characters: 1 sympatric species; key differences in stem morphology, habitat, and elevation
Habitat and range
Habitat: Desert flats, sagebrush scrub
Elevation: 600-1400 m
California counties: Kern, Los Angeles, Ventura, San Bernardino, San Luis Obispo, Inyo, Santa Barbara
Outside California: Oregon, Nevada
Bloom period
Tetrapteron palmeri blooms Apr-May.
How to tell it apart
vs Camissoniopsis: Tetrapteron pods have four pointed wings at top; Camissoniopsis pods lack wings or have rounded angles.; vs Camissonia: Tetrapteron pods are egg-shaped with pointed wings; Camissonia pods are straight cylinders or coiled.; vs Taraxia: Tetrapteron is annual; Taraxia is perennial returning multiple years.
Frequently asked questions
Is Tetrapteron palmeri native to California?
Yes. Tetrapteron palmeri is native to California (recorded as native).
When does Tetrapteron palmeri bloom?
Tetrapteron palmeri blooms Apr-May.
Where in California does Tetrapteron palmeri grow?
Tetrapteron palmeri occurs in Kern, Los Angeles, Ventura, San Bernardino, San Luis Obispo, Inyo, Santa Barbara, at elevations of 600-1400 m.
What plant family does Tetrapteron palmeri belong to?
Tetrapteron palmeri is in the Onagraceae family, genus Tetrapteron.
What habitat does Tetrapteron palmeri grow in?
Tetrapteron palmeri grows in Desert flats, sagebrush scrub.
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.