Desmophlebiaceae and Desmophlebium: A new family and genus of Eupolypod II ferns

Based on an analysis of five plastid markers (atpA, atpB, rbcL, rps4-trnS, trnL/trnL-trnF), we show that Diplazium lechleri is sister to a clade formed by the Hemidictyaceae and Aspleniaceae. Thus, it does not belong to the Athyriaceae where previously classified. A new family, Desmophlebiaceae, and a new genus, Desmophlebium, are described to accommodate this relationship. Morphologically, Desmophlebium is distinguished from Diplazium by the combination of thick 1-pinnate laminae, entire pinnae, decurrent distal pinnae, conform lamina apices (i.e., the terminal segment is similar to the lateral pinnae), and the presence of a submarginal connecting vein. On the basis of morphology, we also assign Diplazium longisorum to the new family and genus. Accordingly, the new combinations Desmophlebium lechleri and D. longisorum are provided. A lectotype is designated for Diplazium parallelogrammum, a synonym of Desmophlebium lechleri. Desmophlebium grows in humid forests from 125 to 1900 m. Desmophlebium lechleri occurs from Panama to north-central and northeastern Brazil, and D. longisorum occurs in Colombia, Ecuador, and Peru.