Phylogenetic revision of Dennstaedtioideae (Dennstaedtiaceae: Polypodiales) with description of Mucura , gen. nov.

We undertook a molecular phylogenetic revision of hayscented ferns (Dennstaedtiaceae: Dennstaedtioideae) using four plastid markers. Our sampling represents ca. 40% of the extant diversity and includes the type species for each of the relevant segregate genera. We coded 20 discrete morphological characters which we used to find diagnosable clades. We show that Dennstaedtia is polyphyletic, with the majority of species forming three morphologically distinct clades, but its type (D.flaccida) is nested within Microlepia. As such, we support the conservation of Dennstaedtiawith a new type, D.dissecta. Following our results, we develop a classification of four genera: Dennstaedtia, Microlepia, Mucura (gen. nov.), and Sitobolium. Beyond the inclusion of D.flaccida, we propose to maintain Microlepia with its current circumscription. Except for a single adventive species in the Neotropics, Microlepia is a Paleotropical genus of about 60 species diagnosed by their distinctive perispore ornamenta...