This is an orange-flowered "jointvetch" that has become widespread in largely subtropical regions around the world but it appears to have originated from southeastern North America (W). It appears to have spread up into the central Mississippi Valley only since 1950. V. Voelker (NP) has discovered it in FULT during 2024: ""well-established on the KY side of Reelfoot Lake and presumably the TN side as well"; see also https:// www.inaturalist.org/ observations/ 229611348. There are also several iNaturalist records since 2019 from s. Ill. The earliest record from Tenn. may be 2011, and the earliest record from Mo. may be 1956 (SERNEC). There are no records yet from Ind.