The moss flora of Japan consists of 1237 species. Of these species, 613 are dioicous, 356 monoicous, 16 dioicous and monoicous, and 252 unknown. In Japan, the frequency of dioicous mosses is the highest among the compared regions : Eastern North America, Britain and Ireland, and New Zealand. All species in Tetraphidales and Funariales are monoicous, but the majority of species in Buxbaumiales and Polytrichales are dioicous.
