Asplenium chihuahuense Baker
Descripción
Roots fibrous, not proliferous; rhizomes short-creeping or suberect; rhizome scales dark brown to blackish, clathrate, 2–3(–4) X 0.2–0.4 mm, entire; fronds clumped, 4–8(–15) cm long; stipes castaneous to atropurpureous, lustrous, 1–5 cm X 0.5–1 mm, 1⁄4–2⁄3 of frond length, glabrous except for scattered filiform scales and minute hairs, non-alate; blades firm-herbaceous to subcoriaceous, ovate-deltate, acute and tapering at apices, rather irregularly pinnate-pinnatifid to 2-pinnate, 2.5–5(–10) X 2–3(–6) cm; rachises reddish brown proximally, green at least in the distal half, dull, glabrescent or with filiform scales to 1 mm long, not winged adaxially; pinnae 4–10 pairs, proximal pinnae deltate to broadly ovate-deltate, 1–4 X 1–2.5 cm, more distal pinnae deltatelanceolate, blades tapering to pinnatifid apices, ultimate segments ovate to spatulate, cuneate proximally, sharply toothed or cleft with ascending teeth, margins thickened and pale; veins not evident except at tips adaxially; indument absent, blades essentially glabrous; sori 1–6 pairs per segment, on both basiscopic and acroscopic sides of midribs of pinnae and pinnules; indusia whitish, 1–3 X 0.2–0.3 mm, margins entire to erose; spores reniform; 2n=216 (Chih).A
Ejemplar revisado
Chih (Correll & Gentry 23042, UC, US; Knobloch 597, 977, US; McVaugh 11508, US; Pringle 1711, NY, UC; Reeves 4877, 4946, ASU; Toolin 1351, ARIZ, US). Dgo (Reeves et al. 5006, ASU).
A
A
Elevación
1800–2600 mA
Ecología y Hábitat
In deep pockets and crevices of rhyolitic rocks and in limestone canyons.A
Categoría IUCN
No incluidaC
Categoría NOM-059-SEMARNAT-2010
No incluidaD
Discusión taxonómica
From artificial hybridization studies, Rasbach et al. (1994) demonstrated that this species is an allohexaploid and possibly formed from hybridization between A. adiantum-nigrum L. var. adiantum-nigrum, a tetraploid, and some unknown diploid. Asplenium adiantum-nigrum L. is principally a Eurasian species but is also found in North America (Ariz, Colo, Utah), where it is very rare, and in Hawaii. It is an allotetraploid derived from hybridization of two European diploids, A. cuneifolium Viv. and A. onopteris L. New World specimens of A. adiantumnigrum (and A. chihuahuense) are generally much smaller (fronds one-third to one-half the length of Old World specimens) than those of A. adiantum-nigrum from elsewhere in the range, but otherwise not very different. Windham (1983) summarized evidence, both cytological and chemical, for treating Eurasian and American plants of A. adiantum-nigrum as conspecific.A