Luisma, a new genus of Grammitidaceae (Pteridophyta) from Colombia

We describe and illustrate a monotypic new genus and species of fern, Luisma bivascularis M.T. Murillo & A.R. Smith (Grammitidaceae), endemic from the Colombian Andes. Luisma is similar to narrow-leaved species of Campyloneurum (Polypodiaceae). However, it agrees with grammitid ferns, in having green, trilete spores (vs. hyaline or yellowish, monolete spores in nearly all Polypodiaceae) and free veins (vs. anastomosing in Campyloneurum). From all Grammitidaceae. Luisma differs, in having two petiolar bundles. Other distinguishing characters include suberect, radially symmetrical rhizomes, sparse hyaline stipe hairs, adaxial hydathodes, and clathrate, setulose rhizome scales.