Fl. W. Lancashire: 450 (1907) [and A. Wilson & Wheldon in Trans. Liverpool Bot. Soc. 1: 6 (1909)].

Type locality: Great Britain, England, West Lancashire, Greygarth Fall, 1906, A. Wheldon & A. Wilson 19 (BM - lectotype; NMW - isolectotype). Lectotypification by Ahti (1965).