Phanerophlebia gastonyi Yatsk.
Descripción
Rhizomes short-creeping to ascending, not branched; rhizome scales bicolorous with broad, dark brown or sclerotic centers and narrow, lighter brown ciliate margins, ovate to ellipticlanceolate, 2.5–6 X 1.5–2 mm; fronds to 25–45(–55) cm long; stipes usually longer than blades, stramineous, with non-overlapping scales 4–6 mm long primarily at the base, caducous distally, reduced hair-like scales uncommon; blades ovate, 14–25 cm long; rachises glabrescent or sparingly scaly; buds absent from axils of distal pinnae; pinnae usually (0–)1–4 lateral pairs, ovate to lanceovate, sometimes somewhat falcate, 7–16 X 2–4 cm, bases obliquely cuneate to rounded, sometimes nearly equilateral, apices acute to attenuate, margins entire to slightly undulate proximally, spinulose-serrulate only in distal half, costae and veins abaxially with rare to sparse minute, hair-like scales 0.5–0.8 mm long on costae, 0.1–0.3 mm long on veins; veins 2–4-branched, with 1–3 series of ± regular to somewhat irregular marginal anastomoses; sori in (1–)2–4 series between costae and pinna margins, inner row 1–4 mm from costa, outer row 2–5 mm from margin; indusia absent; spores 30–42 mm long; 2n=82 (Chis, Oax, as P. juglandifolia, Ver).A
Ejemplar revisado
Chis (Breedlove 21652, DS, MEXU, NY, 30867, DS, MEXU, 31495, DS; Palacios-Rios 2901, UC). Oax (Mickel 3786B, NY, 6044, MO, NY, UC, 6182, MO, NY). Ver (Conant 726, GH, MEXU; Ventura A. 9265, MEXU, NY, 12342, IEB).A
Distribución
México (país) EndémicoA
Elevación
900 – 2200 mA
Ecología y Hábitat
On limestone outcrops.A
Tipo de vegetación
Bosque de neblina/mesófiloA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
This species is exceedingly closely related to P. juglandifolia, differing primarily by the fewer, smaller stipe base scales with a blackened central area. In addition, P. gastonyi always lacks rachis buds (sometimes present in P. juglandifolia) and has veins that are not so highly anastomosing. The morphological differences between these two species seem of less significance to us than the differences between P. nobilis and P. remotispora, which Yatskievych treated as conspecific. Chromosome counts indicate that P. gastonyi is diploid, and one of the probably parents of the tetraploid species, P. juglandifolia (Yatskievych, 1996).
A collection from Oaxaca (Geith 95-M007, NY) has simple blades ca. 10–12 X 2.5–3 cm, and is fertile. The veins are anastomosing, but the slender stipes, ca. 1 mm diam., are nearly devoid of scales and so the specimen is difficult to name. It appears to be a depauperate specimen of P. gastonyi.
Judging by the rhizome scales and absence of rachis buds, a collection (Palma G. 67, XAL) determined by Yatskievych as P. juglandifolia from Veracruz is P. gastonyi. This same collection and Ramírez 527 (XAL), also P. gastonyi, were reported by Palacios-Rios (1992) as the only collections of P. juglandifolia from Veracruz. Hernández M. 5916 (ENCB), from Hidalgo, cited as P. juglandifolia by Yatskievych (1996: 189), also seems to us to be P. gastonyi.
A
A collection from Oaxaca (Geith 95-M007, NY) has simple blades ca. 10–12 X 2.5–3 cm, and is fertile. The veins are anastomosing, but the slender stipes, ca. 1 mm diam., are nearly devoid of scales and so the specimen is difficult to name. It appears to be a depauperate specimen of P. gastonyi.
Judging by the rhizome scales and absence of rachis buds, a collection (Palma G. 67, XAL) determined by Yatskievych as P. juglandifolia from Veracruz is P. gastonyi. This same collection and Ramírez 527 (XAL), also P. gastonyi, were reported by Palacios-Rios (1992) as the only collections of P. juglandifolia from Veracruz. Hernández M. 5916 (ENCB), from Hidalgo, cited as P. juglandifolia by Yatskievych (1996: 189), also seems to us to be P. gastonyi.
A