Argyrochosma formosa (Liebm.) Windham
Descripción
Rhizomes compact, horizontal; rhizome scales 6–9 mm X 0.3 mm, tan to dark orange, linear; fronds to ca. 40 cm tall, clumped; stipes 1⁄4–1⁄2 the frond length, atropurpureous to black, glabrous, terete; blades deltate to ovate-lanceolate, 3–4-pinnate; rachises terete; pinnae 6–9 pairs, alternate to subopposite, glabrous above, gray-green, abaxial surfaces glabrous to glaucous; segments orbicular to inequilaterally cordate, appearing sagittate when folded, articulate, 3–4 mm long and wide, dark axis color stopping abruptly at bases of segments; sori elongate along vein ends, forming a marginal band 0.5–1 mm wide, laminar margins curved, unmodified; fertile segments often folded in half lengthwise; n=2n=81, apogamous (Oax).A
Forma de vida
Rupícola.B
Ejemplares revisados
Ags (Rzedowski 25048, NY). Chis (Ghiesbreght 227, GH, NY, US). Gro (Anderson 12874, NY). Gto (Ventura & López 8900, CAS). Hgo (Frye & Frye 2558, GH, MO, NY). Méx (Bravo 78, MEXU). NL (Pennell 17177, US). Oax (Mickel 4092, NY). Pue (Purpus 1151, NY). Qro (Rzedowski 47536, IEB). SLP (Pringle 3401, GH, LL, MO, NY). Tam (Stanford et al. 882, DS, NY). Ver (Bourgeau 2894, GH, NY, US).A
Elevación
1250 – 2700 mA
Ecología y Hábitat
Dry, rocky, wooded slopes, limestone slopes, steep rocky ravines.A
Tipo de vegetación
Matorral espinosoA
Categoría IUCN
No incluidaC
Categoría NOM-059-SEMARNAT-2010
No incluidaD
Discusión taxonómica
Argyrochosma formosa resembles A. incana in its black frond axes, stalked segments and being widespread, but lacks farina. The other non-farinose species of Argyrochosma in Mexico, A. microphylla, is distinct by its smaller segments (1–3 mm vs. 3–5 mm) and castaneous (vs. black) frond axes.A