New synonyms are proposed in the moss families Orthotrichaceae and Calymperaceae occurring in Réunion Island. Macromitrium rufescens Besch. (Orthotrichaceae) is placed in synonymy with Macromitrium sulcatum (Hook.) Brid. subsp. sulcatum and Syrrhopodon rodriguezii Renauld & Cardot (Calymperaceae) is found to be conspecific with Syrrhopodon mahensis Besch. var. mahensis.