Prodromus of a fern flora for Bolivia. XXVII. Pteridaceae Author Kessler, Michael Systematic Botany, University of Zurich, Zollikerstrasse 107, CH- 8008 Zurich, Switzerland Author Smith, Alan R. University Herbarium, 1001 Valley Life Sciences Bldg. # 2465, University of California, Berkeley, CA 94720 - 2465 Author Prado, Jefferson Instituto de Botânica, Av. Miguel Estéfano, 3687, CEP 04301 - 902, São Paulo, SP, Brasil text Phytotaxa 2017 2017-12-22 332 3 201 250 http://dx.doi.org/10.11646/phytotaxa.332.3.1 journal article 10.11646/phytotaxa.332.3.1 1179-3163 Adiantum scalare R.M.Tryon, Amer. Fern J. 47(4): 141, t. 15. 1957. Range: — Ecuador to Bolivia (LP); Brazil . Ecology: —Rare (4 collections known), terrestrial in montane and lowland evergreen forests, on wet soils; 250– 650 m . Notes: —Very distinctive, closely related to A. villosissimum . Rhizomes short-creeping, nodose; rachis scales lanceolate with copiously ciliate margins; blades pinnate, pinnae narrowly long-triangular, entire, 6–8 times longer than wide, 7–10 pairs per frond, stalked ca. 1–3 mm , apices long-attenuate, pubescent on both surfaces, hairs 1–2 mm long; veins irregularly anastomosing, mostly free; sori 2 per pinna, one on each side of a pinna, continuous, linear, usually not reaching the pinna apex and base; indusia densely pilose, hairs reddish brown.