Adiantum raddianum C. Presl
Descripción
Rhizomes short-creeping, 3–5 mm diam.; rhizome scales dark to light brown, linear-lanceolate, entire, 2.5–3 X 0.5 mm; fronds clumped, ca. 20–45 cm long, laxly arching; stipes dark reddish brown, 10–20 cm X 1–2 mm, ca. 1⁄2 the frond length, glabrous except at bases; blades ovate-deltate to ovate-lanceolate, 2–3-pinnate proximally, 1–2-pinnate distally, tapering to apices; rachises red-brown, glabrous; pinnae 6–9 pairs, pinnae and pinnules with stalks 1–5 mm long; pinnulets obovate to rhomboid, 8–12 mm long, sterile margins dentate, the stalk color passing into pinnulet bases, non-articulate; veins free, forking, ending in sinuses; indument absent on both surfaces; idioblasts absent; sori 4–6 per pinnulet, confined to distal margins; indusia 1–1.5 mm long, reniform to round-reniform, glabrous.A
Forma de vida
TerrestreA
Ejemplar revisado
Chis (1971, Breedlove 21589, DS;1972, 27375, DS). Mich (1985, Leopo 17084, GUADA, UC). Mor (1938, Lyonnet 2565, CAS, MO, UC, US; 1966, Mitastein 168, ENCB, NY; 1994, Pacheco 4669, UAMIZ; 1992, Posadas & Sandoval s.n., UAMIZ; 1993, Riba 1909, UAMIZ; 1991, Sandoval 6, UAMIZ). Oax (1969, Mickel 4020a, NY, UC, 1971, 5999, 6026, NY, UC). Pue (1971, Weber 834, 852, ENCB). Sin (1969, Breedlove 17107, NY). Tlax (1970,Weber 734, ENCB, NY). Ver (Fisher s.n., DS, questionably det.).A
Elevación
800 – 2200 mA
Ecología y Hábitat
On open or lightly shaded banks.A
Tipo de vegetación
Bosque de encino, Selva alta, Selva medianaA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Because of the spottiness and recency of collections of this species in Mexico, we suspect that A. raddianum may not be native, but rather recently introduced; dates of collection, where known, are given in the specimen citations, and all but one of the Mexican collections were made since 1966. Proctor (1985) discussed the possible naturalization of A. raddianum in Jamaica. It is certainly widely cultivated throughout the world, including Mexico, and it would be surprising if it had not escaped. However, nowhere, except possibly in the state of Morelos, does it seem to be common. Adiantum raddianum is closely related to A. poiretii, which see for distinguishing characters.
The Fisher collection cited from Veracruz is immature and lacks rhizome, but it appears to belong to this species (although not matching other Mexican specimens very well); we wonder if it is a horticultural variant of A. raddianum.
A
The Fisher collection cited from Veracruz is immature and lacks rhizome, but it appears to belong to this species (although not matching other Mexican specimens very well); we wonder if it is a horticultural variant of A. raddianum.
A