Streptanthus batrachopus
Tamalpais jewelflower
(c) Arvel Hernandez, some rights reserved (CC BY) · licence
Family: Brassicaceae · Type: Herb · Native
Conservation status: CNPS 1B.3
Streptanthus batrachopus (Tamalpais jewelflower) is a native California herb in the Brassicaceae family, recognized by small size and mottled leaves diagnostic.
Tamalpais jewelflower is a rare (CNPS 1B.3) California native annual found in southern North Coast Ranges and northwestern San Francisco Bay Area on Mount Tamalpais in serpentine barrens and chaparral at elevations of 100 to 600 meters. Flowering from May to June, this plant produces white and purple flowers with distinctive veining, approximately 5 to 8 millimeters long. Growing with slender stems 3 to 17 centimeters tall, the plant can be simple or branched near its base. Its leaves range from basal petioled and mottled to mid-cauline sessile, with lanceolate blades 0.5 to 2.5 centimeters long that are entire or slightly dentate. The fruit is a slender pod 1.3 to 3 centimeters long, spreading to reflexed, with 12 to 22 small seeds.
Identification and appearance
Key characters: 16 sympatric species; small size and mottled leaves diagnostic
Habitat and range
Habitat: Serpentine barrens, chaparral
Elevation: 100-600 m
California counties: Marin, Mendocino, Lake, Colusa
Bloom period
Streptanthus batrachopus blooms May-Jun.
Conservation status
CNPS 1B.3
How to tell it apart
vs Caulanthus: Seed pods are flattened like sword blades versus cylindrical tubes in Caulanthus.; vs Boechera: Robust plants often over 2.5 feet with large flowers (sepals 4-8mm) versus more delicate habit.; vs Claytonia: Mustard family with 4 petals and 6 stamens versus Claytonia with 5 petals.; vs Silene: Mustard family with seed pods versus Silene with inflated capsules and opposite leaves.; vs Lonicera: Herbaceous mustard with alternate leaves versus woody vine with opposite leaves.
Frequently asked questions
Is Streptanthus batrachopus native to California?
Yes. Streptanthus batrachopus is native to California (recorded as native).
When does Streptanthus batrachopus bloom?
Streptanthus batrachopus blooms May-Jun.
Where in California does Streptanthus batrachopus grow?
Streptanthus batrachopus occurs in Marin, Mendocino, Lake, Colusa, at elevations of 100-600 m.
What plant family does Streptanthus batrachopus belong to?
Streptanthus batrachopus is in the Brassicaceae family, genus Streptanthus.
Is Streptanthus batrachopus rare or endangered?
Streptanthus batrachopus carries California Rare Plant Rank 1B.3, state rank S2.
Related species
Other California species in the same genus, family, or bioregion.
- Streptanthus bernardinus — Laguna mountains jewelflower
- Streptanthus brachiatus — Socrates mine jewelflower
- Streptanthus brachiatus ssp. brachiatus — Socrates Mine jewel-flower
- Streptanthus brachiatus ssp. hoffmanii — Freed's jewel-flower
- Streptanthus breweri — Brewer's jewelflower
- Streptanthus callistus — Mount hamilton jewelflower
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.