Galactodenia, a New Genus of Grammitid Ferns Segregated from Terpsichore (Polypodiaceae)

Polyphyly among genera of grammitid ferns has necessitated several nomenclatural innovations. The genus Galactodenia is here described to accommodate two species that were previously placed in Terpsichore, G. delicatula and G. subscabra, and three new species that are here described, G. pumila, G. parriseae, and G. vareschii. In recent phylogenetic studies, the two previously described species form a clade sister to the clade of Lellingeria, Melpomene, and Stenogrammitis, and are not closely related to either Terpsichore or Alansmia, two genera that they have been previously considered close to. Galactodenia can be diagnosed by having concolorous rhizome scales, monomorphic fronds with non-calcareous hydathodes, and hairs that are simple and 2-celled or 1-furcate and 3-celled with large translucent clavate glands that produce a viscid exudate. Most species of Galactodenia are found in montane forests from southern Mexico and the West Indies to Bolivia, from 2,000-4,000 m. One exception to this is G. pumila, which is known only from isolated granite inselbergs at 1,500 m, in southwestern Venezuela. All five species are illustrated, and a distribution map and a key are provided.