Asplenium tryonii Correll
Descripción
Roots thin, wiry, not proliferous; rhizomes suberect to erect; rhizome scales dark brown, clathrate, to 3 X 0.4 mm, entire; fronds clumped, 4–7 cm long; stipes dull reddish brown, lustrous, ca. 1.5 cm X 0.5 mm, 1⁄5–1⁄2 of frond length, with hair-like scales, not winged; blades thick-herbaceous, narrowly lanceolate, 1-pinnate, bearing buds and rooting at bases of terminal segments or from adaxial surfaces of distal pinnae; rachises dull reddish brown, lustrous, sparsely fibrillose, not winged; pinnae oblong to trullate, essentially opposite, 7–12 pairs, proximal pinnae only slightly reduced, to 5 X 3.5 mm, sessile, bases broadly cuneate, apices obtuse, margins crenulate or slightly repand on both acroscopic and basiscopic margins, as well as at tips; veins obscure, tips evident adaxially; indument absent, blades glabrous; sori 2–4 per pinna, on both sides of midveins; indusia 1–2 X 0.8–1 mm, margins somewhat erose-crenulate; spores not seen.A
Ejemplar revisado
Chih (Correll & Gentry 23213, LL).A
Distribución
México (Country) endemicB
Elevación
1900–2200 mA
Ecología y Hábitat
In moss on shaded north-facing ledges.A
Categoría IUCN
No incluidaC
Categoría NOM-059-SEMARNAT-2010
No incluidaD
Discusión taxonómica
Other Mexican species in the Asplenium trichomanes group that bear blade proliferations are A. palmeri, A. stolonipes, A. soleirolioides, A. polyphyllum, and, rarely, A. monanthes. Asplenium palmeri and A. soleirolioides differ from A. tryonii in having flagelliform apices, generally longer fronds, and many more pinna pairs. Asplenium stolonipes and A. monanthes have buds only at the base of proximal pinnae. Asplenium polyphyllum, with buds at the base of distal pinnae, is a much larger species, with many more pinna pairs and larger pinnae. Asplenium tryonii is one of the rarest Mexican spleenworts, still known only from the type an one additional collection.A