Asplenium ultimum A.R. Sm.
Descripción
A. exiguo gemmis apicibus pinnarum et laminarum carentibus, pinnis infimis pinnas contiguas aequantibus, stipitibus longioribus (plerumque 2.5–4 cm longis) et viridibus praeter bases differt. (L. ultimus, last; this species was the last to be recognized and characterized during the preparation of this treatment of Asplenium.).
Roots filamentous, fibrous, not proliferous; rhizomes not known, probably suberect; rhizome scales not seen, but stipe base scales black, clathrate, 1.5–3 X 0.2–0.3 mm, entire; fronds presumably clumped, ca. 6–8 cm long; stipes castaneous and lustrous in the proximal 1 cm, greenish distally, dull, (1.5–)2.5–4 cm X 0.5–1 mm, 1⁄3–2⁄5 of frond length, bearing scattered hair-like scales, not winged; blades mostly 3–4.5 X 1–2 cm, lanceolate, pinnate-pinnatifid, proximal pinnae not or only slightly reduced, the apices neither proliferous nor flagelliform; rachises brownish, with sparse hair-like scales, not winged; pinnae oblong, 6–9 pairs, 5–10 X 3–5 mm, pinnatifid to pinnatisect, apices lacking proliferous buds, pinnules oblong to flabellate, margins subentire to toothed; veins obscure, 1–2-forked in larger pinnules, tips not evident adaxially; indument abaxially of scattered red-brown, appressed, clavate hairs to 0.2 mm long; sori to 5 per pinna, on both sides of midveins, mostly one per pinnule; indusia 1–1.8 X 0.5 mm, margins suberose; spores not seen.A
Roots filamentous, fibrous, not proliferous; rhizomes not known, probably suberect; rhizome scales not seen, but stipe base scales black, clathrate, 1.5–3 X 0.2–0.3 mm, entire; fronds presumably clumped, ca. 6–8 cm long; stipes castaneous and lustrous in the proximal 1 cm, greenish distally, dull, (1.5–)2.5–4 cm X 0.5–1 mm, 1⁄3–2⁄5 of frond length, bearing scattered hair-like scales, not winged; blades mostly 3–4.5 X 1–2 cm, lanceolate, pinnate-pinnatifid, proximal pinnae not or only slightly reduced, the apices neither proliferous nor flagelliform; rachises brownish, with sparse hair-like scales, not winged; pinnae oblong, 6–9 pairs, 5–10 X 3–5 mm, pinnatifid to pinnatisect, apices lacking proliferous buds, pinnules oblong to flabellate, margins subentire to toothed; veins obscure, 1–2-forked in larger pinnules, tips not evident adaxially; indument abaxially of scattered red-brown, appressed, clavate hairs to 0.2 mm long; sori to 5 per pinna, on both sides of midveins, mostly one per pinnule; indusia 1–1.8 X 0.5 mm, margins suberose; spores not seen.A
Ejemplar revisado
Known only from the type collection. NL (Hinton 20142).A
Distribución
México (Country) endemicB
Elevación
2350 mA
Ecología y Hábitat
On limestone rock slide, forming colonies.A
Categoría IUCN
No incluidaC
Categoría NOM-059-SEMARNAT-2010
No incluidaD
Discusión taxonómica
This species is probably most closely related to A. exiguum, but differs by having longer stipes (mostly 2.5–4 cm long), greenish stipes (except proximal ca. 1 cm darkened), without reduced proximal pinnae (which are about as long as the longest pinnae), and absence of buds at the tips of the pinnae and blades. The sori are adjacent and at a narrow angle to the costae, except for single sori along the midribs of the basal acroscopic segment of each pinna.A