Asplenium modestum Maxon
Descripción
Roots thin, fibrous, not proliferous; rhizomes suberect; rhizome scales brown, clathrate, 2 X 0.3 mm, entire; fronds clumped, ca. 8 cm long; stipes green-stramineous, to 2.3 cm X 0.5 mm, 1⁄4–1⁄3 of frond length, bases with a few scattered scales similar to those of rhizomes, not winged; blades thick-herbaceous, oblonglanceolate, 4.5–6 X 1.5 cm, 2-pinnate proximally; rachises greenish to yellowish, glabrous, not winged; pinnae ovate-deltate to irregularly rectangular, 6–8 subopposite to alternate pairs, ca. 10 X 10 mm, short-stalked to 1 mm, proximal pinnae pinnately divided into 3 cuneate lobes, the acroscopic and basiscopic lobes often nearly or quite free, the obtriangular lobes in turn deeply and sharply cleft, more distal pinnae less deeply divided with commonly only the acroscopic lobe free; veins obscure, subflabellate-pinnate, tips evident adaxially; indument absent, blades essentially glabrous; sori 1–3 per lobe; indusia 1.5–2 X 0.5 mm, margins suberose; spores reniform.A
Forma de vida
EpipetricA
Distribución
México (Country) endemicB
Elevación
500 mA
Ecología y Hábitat
On shaded, mossy rocks.A
Categoría IUCN
No incluidaC
Categoría NOM-059-SEMARNAT-2010
No incluidaD
Discusión taxonómica
This taxon is remarkably unlike anything else known from Mexico, and has apparently not been recollected since 1885. This causes one to wonder if it could be a hybrid between two strongly divergent taxa, such as A. trichomanes and A. chihuahuense, both known from Chihuahua. However, SEM photographs (at US) of the spores of the type, by Viane, show that the spores are well formed. In fact, A. modestum closely resembles a European hybrid, A. dolosum Milde (Verh. Zool. Bot. Ges. 14: 165, t. 4. 1864), which is A. adiantum-nigrum L. X trichomanes L. Further study is warranted.A