Recent phyogenetic analyses of grammitid ferns (Polypodiaceae) demonstrated that many genera recognized within this clade are not monophyletic. Focus here is upon circumscription of genera within one clade identified in previous analyses that includes the monophyletic Melpomene, plus portions of two polyphyletic genera, Lellingeria and Terpsichore . Morphology of grammitid ferns is reviewed and used to compile a matrix of 111 qualitative characters for 150 terminals. Phylogenetic analysis of the morphological matrix offer no support for a monophyletic Terpsichore as orginally circumscribed, but otherwise have limited value due to the lack of resolution in the consensus tree. Phylogenetic analyses using chloroplast markers atpB, rbcL, and trnLF, along with 111 qualitative morphological characters resolve this ingroup as monopyletic and sister to a clade that includes Ceradenia, Enterosora, and Zygophlebia. Melpomene is monophyletic, but is nested within Lellingeria in most trees. Ingroup species of Terpsichore form three well supported monophyletic groups that together are paraphyletic with regards to Melpomene plus Lellingeria. Two clades of species currently combined in Terpsichore are recognized as new genera. One of these clades, sometimes referred to as the Terpsichore anfractuosa clade, is described as the new genus Ascogrammitis. Sixteen species of Ascogrammitis are recognized, including five new ones, and new combinations are made for the previously recognized species. A key is provided to distinguish the species, and illustrations are provided for 12 species. The genus occurs primarily in neotropical cloud forests, with the greatest diversity in the Andes.