A total of 29 species, Orthotrichum affine, O. alpestre, O. bartramii, O. consimile, O. crenulatum, O. crispifolium, O. diaphanum, O. erubescens, O. flowersii, O. griffithii, O. gymnostomum, O. microcarpum, O. ohioense, O. pallens, O. patens, O. philibertii, O. pulchellum, O. pumilum, O. pusillum, O. revolutum, O. rogeri, O. schofieldii, O. sinuosum, O. speciosum, O. sprucei, O. stellatum, O. stramineum, O. subpumilum, and O. tenellum, are added to the Japanese Orthotrichum flora. Orthotrichum amabile Toyama, previously considered a synonym of O. erubescens Müll. Hal., is recognized as a good species. Orthotrichum ibukiense Toyama is proposed as a new synonym of O. cupulatum Brid.
Four genera of Bryaceae, Acidodontium Schwaegr., Orthodontium Schwaegr., Pseudopohlia Williams and Schizymenium Harv. are newly found in Japan. Two species of Acidodontium, A. megalocarpum (Hook.) Ren. & Card. and A. longifolium (Par.) Broth., two species of Orthodontium, O. denticulatum Geh. & Hampe and O. pellucens (Hook.) Bruch, Schimp. & Gümbel, Pseudopohlia didymodontia (Mitt.) A. L. Andrews, Schizymenium novoguinense (E. B. Bartram) A. Eddy, three species of Brachymenium, B. alpinum Ochi, B. jilinense T. J. Kop., A. J. Shaw, J.-S. Lou & C. Gao and B. muricola Broth. and Mielichhoferia pusilla (Hook. f. & Wilson) Mitt. are added to the moss flora of Japan. Two new combinations, Schizymenium japonicum (Besch.) Tad. Suzuki and Schizymenium sasaokae (Broth.) Tad. Suzuki are made.
Four species are added to the Fissidens flora of Laos. Fissidens erecto-thorsbornei is new to science. Three species of Fissidens, namely F. parkii, F. nigro-viridis, and F. perpellucidus, are additions to the moss flora of Laos.
Plagiochasma appendiculatum is newly reported from Japan based on examination of herbarium specimens and on field observations in Tokushima Pref., Shikoku. Japanese plants of P. appendiculatum are illustrated and a key to the Japanese species of Plagiochasma is provided.
Based on the molecular phylogenetic analysis and morphological observation, we verify that both Clastobryella tenella and Gammiella ceylonensis are distributed in Japan. Our study suggests that the accession GU327380 (shown as G. tonkinensis in database) is identical to G. ceylonensis. Descriptions with microphotographs based on Japanese plants of these two species are given.