1568 Callitriche hermaphroditica L.

Syn.: C. autumnalis L.

This widespread species belongs to the circumpolar plants (Hultén, Circumpol. II, p. 110, 346f. and map 102). The gaps in the distribution may be due to incomplete knowledge. The closely related population in W. and S. Europe is distinguished as C. truncata Guss. with at least three subspecies (Fl. Eur. 3/1972, p. 124). Cf. also Meusel et al. 1978, map p. 272.