Hymenophyllum plumosum Kaulf., Enum. Fil.

Kessler, Michael & Smith, Alan R., 2017, Prodromus of a fern flora for Bolivia. X. Hymenophyllaceae, Phytotaxa 328 (3), pp. 201-226 : 216

Hymenophyllum plumosum Kaulf., Enum. Fil. 267. 1824.

= Sphaerocionium plumosum (Kaulf.) Copel., Philipp. J. Sci. 67(1): 30. 1938.

Range: — Costa Rica to Colombia and Bolivia (CO, LP); southeastern Brazil.

Ecology: —Uncommon; pendent epiphyte in humid forests, rarely on earth banks; 1400–3300 m.

Notes: — Hymenophyllum multialatum C.V.Morton , from Colombia to central Peru, may occur in Bolivia. It differs from H. plumosum by much broader and conspicuous lamellae, and somewhat less dense pubescence. The veins of H. plumieri have ill-defined lamellae; these take the form of low outgrowths borne along the abaxial or sometimes adaxial sides of the veins, contiguous to, but not in the same plane with, the leaf tissue. The lamellae are often difficult to discern and are hidden by the dense hairs; the wings are most easily found on the older (proximal) pinnae where hairs may have partially fallen off. The species is very similar to H. speciosum , which lacks lamellae.