Selaginella basipilosa Valdespino
Descripción
Stems prostrate, forming rather loose mats, dorsiventral, 5–17 cm long, 0.4–0.8 mm diam., not articulate, not flagelliform, not stoloniferous, 2–3 times branched, branches horizontal or curling upward (in dry conditions); rhizophores borne throughout stem length, 0.2–0.3 mm diam.; leaves of one kind (isophyllous) throughout; upperside leaves spreading, green to green-grayish, or light brown (in old leaves), narrowly deltate-lanceolate to linear-lanceolate, slightly falcate on lateral rows, 1.7–2.5 X 0.4–0.6 mm (wider at base), bases abruptly adnate (distinct from stems), truncate to slightly rounded, strongly pubescent, hairs often running along ridges bordering abaxial grooves, margins ciliate, cilia hyaline, 0.1–0.3 mm, apices acuminate to shortcuspidate, hyaline, 0.1–0.2 mm; underside leaves buff to light brown or golden brown, lanceolate, 2.5–3.5 X 0.5–0.9 mm (wider at middle), bases rounded to subcordate, weakly decurrent, pubescent, rarely glabrescent, apices acuminate, shortaristate, aristae hyaline, whitish or yellowish, 0.1–0.4 mm, margins ciliate, cilia hyaline, denticulate distally; strobili quadrangular, 4–6 mm long; sporophylls monomorphic, green to grayish green; megasporangia usually in one ventral row; microsporangia in two dorsal rows and one ventral row; megaspores lemon-yellow, shallowly reticulate-rugose, 330–400 µm diam.; microspores light-orange, granulose, 40–53 µm diam., shed mostly in tetrads.A
Forma de vida
Epipétrica.A
Ejemplar revisado
Oax (Rowell et al. 17M489, MEXU, TEX; Valdespino et al. 1126, BM, MEXU, MICH, MO, NY, PMA, UC, US).A
Distribución
México (país) EndémicoA
Elevación
1500 mA
Ecología y Hábitat
On dry, rocky slopes.A
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Selaginella basipilosa belongs to subg. Tetragonostachys series Eremophilae. Among the species of series Eremophilae it is most closely related and easily confused with S. landii. Selaginella basipilosa differs from S. landii by its narrowly lanceolate to linearlanceolate dorsal leaves (vs. ovate-deltate to ovate-lanceolate), with apices acuminate to short-cuspidate (vs. muticous, toothed tip); margins ciliate throughout (vs. short-ciliate at bases and denticulate toward apices), cilia and teeth hyaline (vs. white to white-hyaline); sporophylls with upper surface minutely papillose and seemingly smooth (vs. warty, especially along ridges bordering abaxial grooves); sporophyll apices acute to shortacuminate (vs. long-attenuate and aristate); and ventral leaf bases pubescent (vs. glabrous). Additionally, the distal face of megaspores in S. basipilosa has an open reticulum (vs. close reticulum) with low ridges (vs. high ridges) and the microstructure is foveolate with coarse elements (vs. smoother elements).A