The present paper provides a monograph of Elaphoglossum subsect. Muscosa, a monophyletic group supported by molecular phylogenetic analyses. The monograph includes keys, full synonymy, descriptions, representative specimens examined, an index to collectors’ names and numbers, illustrations, spore photomicrographs, and distribution maps for all species. Morphologically, the subsection is recognized by scaly rhizomes, petioles and laminae, obtuse leaf apices, and spores that are about twice as long as in other species of Elaphoglossum. Fifteen species of subsect. Muscosa are here recognized, with no subspecies or varieties. All of the species are Neotropical occurring from southern Mexico to Bolivia and Southeastern Brazil, with three species in the West Indies. Most of the species occur in the Andes from 1500–4000 m, primarily in cloud forests and paramos. Three new species are described: E. novogranatense, E. oreophilum, and E. quisqueyanum. The name E. glabrescens A.Vasco, nom. & stat. nov. is proposed. Lectotypes are designated for E. aschersonii, E. bellermannianum, E. blandum, E. caulolepia, E. corderoanum, E. decipiens, E. ellipsoideum, E. engelii, E. gardnerianum, E. lehmannianum, E. muscosum, E. viscidulum, E. yarumalense, and E. yatesii.