Orbexilum stipulatum (Torrey & Gray) Rydberg. Subgenus: Orbexilum. Hab: Limestone glades. Dist: So far as is known, once endemic to Rock Island in the Ohio River, Jefferson Co., KY, and now presumed extinct because of near obliteration of the only known site by dam-building and industrial construction (Baskin, Isely, & Baskin 1986).
Origin/Endemic status: Endemic
Synonymy: = C, K1, K3, K4, SE3, Grimes (1988), Grimes (1990), Isely (1998), Turner (2008); = Psoralea stipulata Torr. & Gray – F, G