Systematics of California’s critically endangered Nipomo lupine (Lupinus nipomensis)

Lupinus nipomensis, the Nipomo lupine, is an endangered plant species faced with an alarming vulnerability to extinction from invasive species, habitat fragmentation, and variable abiotic factors such as rainfall and temperature. In Munz's 1963, The California Flora, Nipomo lupine was determined to be a divergent population of Bajada lupine (Lupinus concinnus), creating uncertainty about the species resolution to the present day. Furthermore, the taxonomic ambiguity surrounding Nipomo lupine has hindered conservation efforts. Here, we provide morphological and phylogenetic evidence to demonstrate that Lupinus nipomensis is a clearly circumscribed species and separate lineage from other clades, particularly Lupinus concinnus.