Decrypting phylogenetic placement and specific level relationships from a recent radiation for the CNPS listed rare plant Mentzelia polita (Loasaceae), with Dylan Cohen: The Mentzelia section Bartonia (Loasaceae) is the result of a rapid recent radiation throughout the Intermountain Ranges and deserts of the western United States. Mentzelia polita is taxonomically placed within section Bartonia and is listed by CNPS as 1B.2, rare or endangered in California and elsewhere. The ‘subshrubby' Bartonia clade includes M. polita and occurs primarily within the Mojave Desert. Historically this group has been challenging, with distinctions between taxa subtle at best. Problematic species include M. polita, M. oreophila, and M. leucophylla. Menztelia polita and M. oreophila both occur in California and Nevada, while M. oreophila ranges more widely. Both of the former taxa have been suggested to differ morphologically between their CA and NV populations. Furthermore, M. leucophylla is a federally listed endemic only found in Ash Meadows, NV, but has been suggested to occur in habitats similar to Ash Meadows within boarder California. Geographically, Ash Meadows is less than ten miles from the boarder of CA. Mentzelia leucophylla also has been confused historically with M. oreophila. Restriction Site Associated DNA Sequencing (RAD-Seq) is used to elucidate relationships among members of the Mentzelia section Bartonia ‘subshrubby' clade. Further considerations are given towards a conservation plan for ‘M. polita' within California.