Phanerophlebia C.Presl
Descripción
Rhizomes compact, shortcreeping or ascending to erect, scaly; fronds small to mediumsized, less than 100(–135) cm, clumped; stipes scaly, especially at the bases, filiform-scaly to glabrescent distally; blades 1-pinnate, each with a conform terminal pinna; rachises usually with at least a few persistent filiform or lanceolate scales; pinnae coriaceous or chartaceous, spinulose-serrate or less commonly entire at margins, with tan appressed hairs 0.1–0.5 mm and hair-like scales to ca. 2 mm on the veins and tissue between the veins; veins pinnately branched, free to casually or sometimes regularly anastomosing, branches strongly upcurved and running toward the pinna margins; sori round, in mostly 2–4 series between costae and margins, indusiate or exindusiate in a few species, indusia firm, peltate, often caducous; spores bilateral, with cristate perispore; x=41.A
Forma de vida
o epipétrica. TerrestreA
Distribución
México (país) Nativo y no endémicoA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Phanerophlebia is a neotropical genus of 9 species, from southwestern United States (Texas to Arizona) to northern South America and Hispaniola; all but one species (P. haitiensis C. Chr., from Hispaniola and Honduras) occur in Mexico. Most species grow in mesic forests at middle to higher elevations, often in calcareous rock crevices or calcareous soil.
Phanerophlebia is clearly a member of the large dryopteroid clade, also including Polystichum, Dryopteris, Arachniodes, and probably Stigmatopteris and Ctenitis in Mexico; Adenoderris may also be a part of this clade. Phanerophlebia has traditionally been distinguished from Cyrtomium on the basis of free vs. netted veins, but some phanerophlebias have netted veins and some cyrtomiums have free veins. The distinction of Phanerophlebia (1-pinnate fronds with multiseriate sori) from Polystichum (many narrow pinnae) is tenuous, and the entire group (polystichoid ferns) needs more work to see if there are valid generic distinctions. Yatskievych et al. (1988) and Stein et al. (1989) provided evidence from chloroplast DNA restriction site differences that the morphological similarities between Phanerophlebia and Cyrtomium are the result of convergent evolution. Therefore, if lumping is to be done, Phanerophlebia should merged with Polystichum rather than with just Cyrtomium. Little and Barrington (2003) have evidence that Phanerophlebia is monophyletic and the sister of Polystichopsis. This clade forms the sister group of Polystichum, including Cyrtomium and Cyrtomiopsis, which nest within Polystichum.
A
Phanerophlebia is clearly a member of the large dryopteroid clade, also including Polystichum, Dryopteris, Arachniodes, and probably Stigmatopteris and Ctenitis in Mexico; Adenoderris may also be a part of this clade. Phanerophlebia has traditionally been distinguished from Cyrtomium on the basis of free vs. netted veins, but some phanerophlebias have netted veins and some cyrtomiums have free veins. The distinction of Phanerophlebia (1-pinnate fronds with multiseriate sori) from Polystichum (many narrow pinnae) is tenuous, and the entire group (polystichoid ferns) needs more work to see if there are valid generic distinctions. Yatskievych et al. (1988) and Stein et al. (1989) provided evidence from chloroplast DNA restriction site differences that the morphological similarities between Phanerophlebia and Cyrtomium are the result of convergent evolution. Therefore, if lumping is to be done, Phanerophlebia should merged with Polystichum rather than with just Cyrtomium. Little and Barrington (2003) have evidence that Phanerophlebia is monophyletic and the sister of Polystichopsis. This clade forms the sister group of Polystichum, including Cyrtomium and Cyrtomiopsis, which nest within Polystichum.
A