Cephalantholejeunea temnanthoides (R.M.Schust.) R.M.Schust., the only known member of the genus Cephalantholejeunea R.M.Schust. (Lejeuneaceae, Hepaticae), is a rare Amazonian rheophyte with entire underleaves and unique, bisexual branches consisting of a terminal androecium with 2–6 female branches at its base, the gynoecial branches with only one gynoecium and lacking innovations. Sporophytes described here for the first time indicate that the genus is a member of the subfamily Ptychanthoideae, tribe Ptychantheae, not of the subfamily Lejeuneoideae as was uniformly believed.

Communicating Editor: Alan Whittemore