Pleopeltis riograndensis (T.Wendt) E.G.Andrews & Windham
Descripción
Rhizomes creeping, 1 mm diam.; rhizome scales bicolorous, centers clathrate and black, lanceolate to linear-lanceolate, 2–3 X 0.3–0.5 mm, margins tan, denticulate; fronds (3–)5–13 cm long, subapproximate; stipes 1⁄3(–1⁄2) the frond length, tan to stramineous, with scattered lanceolate scales 2 mm long and smaller ovate scales 0.5 mm long, centers bicolorous, clathrate, marginal cells pale, thin-walled, with coarse teeth, tips attenuate; blades pinnatisect, narrowly deltate to oblong, 1–4 cm wide, decurrent; pinnae 2–9 pairs, narrowly oblong, 0.5–2.4 cm X 2–4 mm; adaxial blade surfaces with scattered to slightly imbricate ovate to deltate scales, bases with thick-walled brown central cells and paler margins, with coarse, often forked teeth, apices often attenuate; adaxial blade surfaces glabrous; venation obscure; sori round, medial; sporangia glabrous.A
Ejemplar revisado
(Related to the synonym Polypodium riograndense) Chih (Correll & Gentry 23052, US; Knobloch 5945, NY; LeSueur 416, US; Pringle 443, NY [some sheets of this number are P. thyssanolepis]; Reeder et al. 3477, ARIZ; Spellenberg et al. 12119, UC). Coah (Henrickson 11652, LL; Johnston et al. 11888b, LL). Son (Fishbein 1784, ARIZ; Harvey 1706, US).A
Elevación
1500 – 2400 mA
Ecología y Hábitat
Rock crevices or gravelly soil.A
Tipo de vegetación
Bosque de pino-encinoA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
(In relation to the synonym Polypodium riograndense) In contrast to P. thyssanolepis, the venation in this species is mostly free, laminae less scaly (not concealing the blade surfaces), stipes are only sparsely scaly, and the proximal pinnae are alternate. The stipe scales are mostly ovate or lance-ovate (vs. mostly suborbicular). There are some intermediate specimens in Chihuahua (Wendt, 1980). Polypodium thyssanolepis is widespread in Mexico, reaching its northern limit in central Chihuahua, whereas P. riograndense is limited in Mexico to Coahuila, Chihuahua, and Sonora.
This species is distinct from P. fallacissimum in the coarse, often forked scale teeth and pinnae more perpendicular to the rachises. From P. thyssanolepis, P. riograndense differs in the small plant size, sparse stipe scales, mostly free veins, and alternate proximal pinnae.
A
This species is distinct from P. fallacissimum in the coarse, often forked scale teeth and pinnae more perpendicular to the rachises. From P. thyssanolepis, P. riograndense differs in the small plant size, sparse stipe scales, mostly free veins, and alternate proximal pinnae.
A