Polypodium christensenii Maxon

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Polypodium christensenii Maxon

Descripción

Rhizomes creeping, 3–4 mm diam.; rhizome scales orange-tan, lanceolate, attenuate, the margins inrolled, entire, 6–7 X 1–1.2 mm; fronds 65–120 cm long, 1 cm or more distant; stipes 1⁄4–1⁄2 the frond length, dark brown, with short, whitish hairs, 0.1 mm; blades pinnatisect, apices usually pinnatifid to blade tips, narrowly oblong, 15–30 cm wide; pinnae 23–30 pairs, broadly adnate to rarely narrowly adnate proximally, linear, 7–18 cm X 1.4–2.2 mm; margins crenulate-serrulate; abaxial surfaces with dense erect hairs ca. 0.5 mm long, hairs on costae 0.6–1 mm; adaxial surfaces with hairs ca. 0.5 mm long; venation free, with rare anastomoses, vein ends conspicuous; sori round, medial; sporangia with hairs 0.1 mm; 2n=74 (Chis).A

Forma de crecimiento

Hierba

Forma de vida

EpífitaA

Nutrición

Autotrófica

Ejemplar revisado

Chis (Breedlove 32006, DS, NY, 34803, 41087, CAS, DS).A

Distribución

Centroamérica: Guatemala PresenteA, México (país) Nativo y no endémicoA

Elevación

2000 – 2400 mA

Ecología y Hábitat

On mossy banks.A

Tipo de vegetación

Bosque de neblina/mesófiloA

Categoría IUCN

No incluidaB

Categoría NOM-059-SEMARNAT-2010

No incluidaC

Estatus del taxón

(A) Como definida actualmente, probablemente una entidad natural (monofilética)

Discusión taxonómica

Polypodium christensenii is very similar to P. puberulum but seems to differ in the larger fronds to 1.2 m long; stipes dark brown; pinnae irregularly crenulate-serrate along margins; and perhaps in rhizome scales without a greatly expanded base, not as long-attenuate, spreading. This group of free-veined, hairy polypodiums (including P. subpetiolatum) is badly in need of revision.A

Bibliografía

A. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
B. IUCN 2022: The IUCN Red List of Threatened Species. Versión 2022-2
C. SEMARNAT 2019: MODIFICACIÓN del Anexo Normativo III, Lista de especies en riesgo de la Norma Oficial Mexicana NOM-059-SEMARNAT-2010: 101 pp. – https://www.dof.gob.mx/nota_detalle.php?codigo=5578808&fecha=14/11/2019#gsc.tab=0 [accessed 2023-05-04 06:16]