Further taxonomic studies on the families Calymperaceae (Musci) and Orthotrichaceae (Musci) in the bryoflora of Réunion Island, with notes on taxa from other islands in the western Indian Ocean

The systematics and geographical distribution of some taxa in the moss families Calymperaceae and Orthotrichaceae that occur in Réunion and neighbouring islands are revised. In the family Calymperaceae, three new subspecies are proposed: Calymperes taitense (Sull.) Mitt. subsp. pachyloma (Hampe ex Müll. Hal.) L. T. Ellis, comb. et stat. nov., Syrrhopodon hispidocostatus Renauld et Cardot subsp. artsii L. T. Ellis, subsp. nov. and S. flexifolius Mitt. subsp. reunionensis L. T. Ellis, subsp. nov.; three further new records for Réunion Island are cited: Calymperes pallidum Mitt., Syrrhopodon dimorphophyllus L. T. Ellis, S. vardei L. T. Ellis, and the presence and geographical distribution in the East African Islands is discussed of Calymperes couguiense Besch., Syrrhopodon asper Mitt., S. africanus (Mitt.) Paris, S. gardneri (Hook.) Schwägr., and S. pulcher W. D. Reese. In the family Orthotrichaceae, new synonymy and distribution records are reported for the genus Macromitrium. Several new synonyms are proposed under Macromitrium microstomum (Hook.et Grev.) Schwägr., M. serpens (Hook. et Grev.) Brid., M. mauritianum Schwägr. and M. pallidum (P. Beauv.) Wijk et Margad. Macromitrium fimbriatum (P. Beauv.) Schwägr. var. chloromitrium Besch. is recognised as a species in its own right, M. chloromitrium (Besch.) Wilbraham, comb. et stat. nov., and is newly recorded from Réunion. Macromitrium belangeri Müll. Hal. is excluded from the Réunion Island’s moss flora.