Taxon Report

Streptanthus batrachopus Morrison

Tamalpais jewelflower

Print Report

Taxon Summary

Streptanthus batrachopus, commonly known as Tamalpais jewelflower, is a annual herb in the Brassicaceae that is found only in California. It occurs within Chaparral, and Closed-cone coniferous forest, growing at elevations from 305 to 650 meters. Streptanthus batrachopus is ranked 1B.3, Plants Rare, Threatened or Endangered in California and Elsewhere; Not very threatened in California.

Classification


Scientific Name:	Streptanthus batrachopus Morrison
Common Name:	Tamalpais jewelflower
Family:	Brassicaceae
Element Code:	PDBRA2G050
USDA Plants Symbol:	STBA4
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Apr-Jul	Apr-Jul
Elevation:	305-650 (1000-2135)
General Habitats:	Chaparral, Closed-cone coniferous forest
Microhabitat:	Serpentine
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.3
Global Rank:	G2
State Rank:	S2
State List:	None
Fed List:	None
Other Status:	SB_UCSC
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	8
Element Occurrence Ranks:
Excellent (A)	1
Good (B)	2
Fair (C)	2
Poor (D)	0
None (X)	0
Unknown (U)	3

Location


California Endemic: True
California Counties and Islands: Name (Code)
Marin (MRN)
Quads: Name (Quad Code)
Bolinas (3712286), San Geronimo (3812216), San Rafael (3712285)

Threat List Data from the CNDDB


Threat List Total:	3
EOs with Threat Listed:	Total EOs	% of EOs
	3	38 %
Foot traffic/trampling	3	37%
Other	1	12%
Recreational use (non-ORV)	1	12%

Notes



Known from fewer than ten occurrences in the Mt. Tamalpais area. Similar plants from the southern North Coast Ranges may be an undescribed new taxon. Intergrades with S. barbiger.
Threats:

Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 31 October 2025].