Pelazoneuron albicaule (Fée) A.R.Sm. & S.E.Fawc.
Descripción
Rhizomes long-creeping, to 8 mm diam.; fronds mostly 150–200 cm long; stipes glabrous or glabrescent, epaleate or nearly so, 25–100 cm X 4–7 mm; blades to 100 cm long, often narrowed rather abruptly toward the somewhat elongate tips; rachises usually glabrous or sparsely hairy; pinnae (10–)15–35 X (0.9–)1.4–3.5 cm, lowermost the longest, never auriculate, narrowed at bases especially along basiscopic side, with 2–4 basiscopic segments often reduced, incised 0.5–0.8 the way to the costae; segments oblique, falcate, acute at tips, (2–)3–4 mm wide at bases; veins 10–20 pairs per segment, proximal 1–2 pairs of veins from adjacent segments connivent at the raised sinus membrane; indument abaxially of a few dark-castaneous short-hairy scales on costae, hairs absent or relatively sparse, 0.1–0.2 mm long on costae and costules, veins and tissue between veins glabrous, adaxially the blades glabrous except for sparse hairs 0.1 mm long along costae; sori medial to supramedial, with indusia glabrous or infrequently sparsely hairy with hairs 0.1–0.15 mm long, usually drying pinkish or reddish brown.A
Forma de vida
TerrestreA
Ejemplar revisado
(Related to the synonym Thelypteris albicaulis) Chis (Matuda 5178, LL, MEXU, US). Gro (Hinton 9921, ARIZ, LL, TEX, US; Soto N. & Martínez 5769, ENCB, UAMIZ). Jal (Wilbur & Wilbur 1856, MEXU, US). Méx (Schaffner 84, P). Mich (Hinton 15584, ARIZ, LL, TEX, US). Mor (Lyonnet 2865, MEXU, US). Oax (Wendt et al. 4700, CHAPA, MEXU; Yatskievych 83-402, ARIZ, UC). Ver (Langman 3428, MEXU, US).A
Distribución
México (país) EndémicoA
Elevación
1200 – 2200(– 3050) mA
Ecología y Hábitat
Wooded banks, near streams.A
Tipo de vegetación
Bosque de pino-encinoA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
(In relation to the synonym) Thelypteris albicaulis is most closely related to T. puberula, from which it differs in the glabrous indusia and glabrous or sparsely hairy costae abaxially. From T. hispidula, T. dentata, and T. kunthii, it differs in lacking hairs and glands on the blades adaxially (costae excepted). Another close relative is T. grandis A. R. Sm., from southern Central America, South America, and the Greater Antilles. Previously, Smith (in Mickel & Beitel, 1988) applied the name T. grandis var. pallescens to very large-fronded specimens with short-hairy costae and indusia from western Mexico. We now believe such plants are better referred to T. albicaulis, and that the true T. grandis var. pallescens is confined to southern Central America, South American Andes, and the Greater Antilles. The following Mexican specimens are representative of this hairy variant of T. albicaulis: Jal (McVaugh 13775, MICH, US; Mexia 1764, CAS, UC; Rzedowski 27500, ENCB). Oax (Somers et al. 319, NY).
Thelypteris albicaulis is suspected of hybridization with T. puberula (Smith, 1971). Several putative hybrids have been seen from Oaxaca: Kenoyer 1554, GH; Mickel 5078b, NY; Smith 489, MEXU, 490, UC. This last collection has been examined cytologically and found to show about 36II + 36I at meiosis. Another putative hybrid is from Michoacán: Arsène 5540, US. A putative hybrid between T. albicaulis and T. ovata is Breedlove 22172 (DS), from Chiapas. Spores of all these hybrids are malformed, and the various hybrids show morphological intermediacy between the suspected parents.A
Thelypteris albicaulis is suspected of hybridization with T. puberula (Smith, 1971). Several putative hybrids have been seen from Oaxaca: Kenoyer 1554, GH; Mickel 5078b, NY; Smith 489, MEXU, 490, UC. This last collection has been examined cytologically and found to show about 36II + 36I at meiosis. Another putative hybrid is from Michoacán: Arsène 5540, US. A putative hybrid between T. albicaulis and T. ovata is Breedlove 22172 (DS), from Chiapas. Spores of all these hybrids are malformed, and the various hybrids show morphological intermediacy between the suspected parents.A