This globally rare species is known mostly from plowed, eroded, rocky or otherwise bared soils on river-bottoms and calcareous glades in c. Tenn. (FNA 7). See also O'Kane & Al-Shehbaz (2002) for support of new generic circumscriptions. The record from Ala. is dubious (Chester 2017). The record from Ky. has been considered adventive (Al-Shehbaz 1987). But this single locality in Ky. is merely a outlying downstream extension of a much larger populations along the Cumberland Rv. and its tributaries in Tenn. Chester (1982, 1992) discovered this small population in 1981on alluvial bottomland at the terminus of LBL Road 204 between Crockett Bay and Prior Bay, just north of the state line. The species has not been recorded at this site or elsewhere in the region since 1985, despite much searching (Chester 2017).