The Streptanthus morrisonii complex is a six-taxon group of closely related serpentine rock outcrop endemics from Lake, Napa, and Sonoma counties of California, USA. Two new subspecies (S. morrisonii subsp. kruckebergii and S. brachiatus subsp. hoffmanii) from Lake County, California, are described. The relationship of these taxa to others in the section is reviewed and descriptions and a key are provided.
Dolan, R. W. & LaPré, L. F. (1989). Taxonomy of Streptanthus sect. Biennes, the Streptanthus morrisonii complex (Brassicaceae). Madroño, 36 (1), pp. 33-40. Available from: http://digitalcommons.butler.edu/facsch_papers/45.