Bazzania calypogeoides (Marchantiophyta)—a peculiar new taxon from Eastern Hengduan (China)

Bazzania calypogeoides is described from several localities on the eastern edge of the Hengduan mountain system in Sino-Himalaya. The species is characterized by shallowly emarginate underleaves, strongly convex leaves, curved to the ventral side and with a very short sinus resulting in two unequal lobes. The position of the species was assessed using morphological and molecular genetic analyses. A morphologically similar species, B. wooroonooran, is known from Australasia and eastern Melanesia, but differs in several features. A description of the species, illustrations and discussions on the ecology and geography of the new taxon are provided.