A total of 27 species are added to the Japanese Fissidens flora. Two of these species, F. curvato-wichurae and F. kimurae, are new to science. The remaining 25 species, F. amoenus, F. aphelotaxifolius, F. arcticus, F. bourgaeanus, F. bushii, F. coacervatus, F. curnovii, F. elongatus, F. exilis, F. gedehensis, F. gracilifolius, F. inconstans, F. incurvus, F. kurzii, F. laxitextus, F. monguillonii, F. pseudoclosteri, F. pusillus, F. rivularis, F. rufulus, F. subbasilaris, F. sublimbatus, F. tenellus var. tenellus, F. viridulus, and F. wichurae, are additions to the moss flora of Japan.
Fissidens in Japan includes 74 species and 5 varieties. These species belong to four subgenera: Fissidens (47 species), Aneuron (1 species), Neoamblyothallia (4 species), and Pachyfissidens (22 species). Keys to the subgenera, sections, and species of Fissidens are provided.
The genus Pterogonium Sw. was newly found in Japan. Four species are added to Japanese moss flora. P. tenellum is new to science. P. gracile, P. tsinlingense and P. coreense are new additions to the moss flora of Japan.