The only plants referable to this northeastern annual that are currently known in Ky. are along trails close to Sky Bridge at Red River Gorge in WOLF. Several colls. have been made from this population, including 16 sheets with 3-4 stems per sheet for George Mason University in 2013; the reason for this massive gathering of an endangered species is unknown. Old unverified records come from McMurtrie (1819), Rafinesque (1840) and later authors. There is also a coll. from ROWA (MDKY) with dubious label data (Campbell et al. 1992). There has been uncertainty about the treatment of varieties within M. lineare, and the plants mapped here have been named var. lineare or var. pectinatum (Pennell) Fern. by some authors. The more northern var. lineare may not be worth distinguishing, but var. pectinatum is a more distinct taxon known only from the Atlantic Coastal Plain (W).