Monographs Details: Melpomene pilosissima (M.Martens & Galeotti) A.R.Sm. & R.C.Moran var. pilosissima
Authority: Lehnert, Marcus. 2013. Grammitid ferns (Polypodiaceae). II. . Fl. Neotrop. Monogr. 112: 1--121. (Published by NYBG Press)
Synonyms:Polypodium pilosissimum M.Martens & Galeotti, Ctenopteris pilosissima (M.Martens & Galeotti) Copel., Grammitis pilosissima (M.Martens & Galeotti) C.V.Morton, Xiphopteris pilosissima (M.Martens & Galeotti) Crabbe, Polypodium pilosissimum var. glabriusculum Mett., Polypodium pilosissimum var. hirsutum Mett.
Description:Species Description - Plants epiphytic or epilithic, rarely terrestrial. Rhizomes short, ascending to erect, 0.8-1.2 mm diam. Fronds 14-18 cm long, patent to stiffly pendent, inserted onto the rhizomes at acute angles, closely arranged (internodes 0.5-2.0 mm), caespitose. Rhizome scales to 5.5 x 0.6 mm, (8—)10—12(—16) cells wide across bases, clathrate, dark brown to brown, strongly iridescent, lanceate, narrowly cordate basally, acute to attenuate at tips; apical cells 1—6(—8), linearly or furcately arranged. Petioles 26-55 mm long, 0.6 mm diam., terete or weakly marginate from the laminar bases, with many, dark brown, setiform hairs 0.8-3.0 mm long, simple and branched clavate hairs of crosiers and young fronds sometimes persistent on older fronds. Laminae to 125 x 8-21 mm (ca. 2/3 of frond length), firm-herbaceous to chartaceous, usually matte, narrowly elliptic (broadest at and/or below the middle), rounded to broadly cuneate at bases, short-acute at tips. Rachises dark brown to black, planar adaxially, hemispherically protruding abaxially, moderately to densely hairy abaxially and in the proximal half adaxially. Largest segments 5.0-12.0 x 1.4—2.6 mm (4-5 times longer than as broad), segments weakly ascending (75-80°), basally inequilateral, fully adnate, long-deltate to oblong, the tips obtuse; midveins not apparent, or obscurely so abaxially in dried specimens; proximal 1-3 segment pairs markedly smaller than the following segments, but not auriculiform; hairs few to many, evenly distributed on the abaxial laminae, always some along the margins, at least one at the segment tips, adaxially absent; hairs not clustered in sori; hydathodes well developed. Sori 1-6 pairs per segment, with 1-3 setiform hairs 1.5-2.0 mm long in them and several around them.

Distribution:Veracruz Mexico North America| Chiapas Mexico North America| Oaxaca Mexico North America| Guerrero Mexico North America| San José Costa Rica Central America| San Marcos Guatemala Central America| Francisco Morazán Honduras Central America| Mérida Venezuela South America| Trujillo Venezuela South America| Boyacá Colombia South America| Cundinamarca Colombia South America| Risaralda Colombia South America| Santander Colombia South America|