The plants in this population keyed unambiguously to S. cordatus var. piutensis in the Jepson eFlora Key to Streptanthus, the FNA key, and Reed Rollin's 1993 'Cruciferae of Continental North America'. The diagnostic characters are: cauline leaves sessile, clasping-auriculate; racemes ebracteate and lacking a terminal 'flag' of sterile flowers; fruit glabrous; perennial; all stamens fertile; cauline leaves reduced distally; fruit spreading to ascending; stamens in 3 unequal-length pairs (not tetradynamous); basal leaves dentate; mid-cauline leaves lanceolate and acute.

Another informative reference for this taxon is Greene & Sanders(2006).

The plants in this population were growing on a reddish substrate of scree, talus, and clay derived from a geographically localized Mesozoic-age roof pendant of gabbro...see the interactive CA geologic map at this link (and enter lat/log coords 35.564 -118.492 in the 'Esri World Geocoder' field). See also the 2015 paper 'Gabbro Soil-Plant Relations in the California Floristic Province' for an informative discussion of gabbro soils and plant endemism (the Piute Mountain gabbro and S. cordatus var. piutensis are briefly discussed on page 80). Much detail on the geology on the olivine gabbro body south of Bodfish can be found in this 1987 USGS report (see pg. 7, maps on pp. 38 & 39).