Abstract
The fern family Didymochlaenaceae contains the genus Didymochlaena only. This genus is generally believed to comprise one species only, while morphological polymorphism in this species has long been observed. Here we conducted a taxonomic revision of Didymochlaena from Madagascar and recognized six species including two new species, three new statuses, and one new combination. A key to the Malagasy species and detailed descriptions of all species recognized are provided.