Parablechnum schiedeanum (C. Presl) Gasper & Salino
Descripción
Rhizomes large, woody, suberect; rhizome scales 10–30 X 2–10 mm, light brown, ovate to lanceolate, entire; fronds strongly dimorphic, to 200 cm long, clumped; stipes (0.5–)25–80 cm X 3–7 mm, 1⁄3–1⁄2 the frond length, stramineous or less often purplish or dark-streaked, usually smooth, at bases with scattered scales resembling rhizome scales; sterile blades subcoriaceous to coriaceous, 26–100 X (10–)20–40 cm, 1-pinnate, proximal pinnae not reduced, terminal pinna conform; rachises stramineous, papillate or corrugate, bearing sparse ovate to lanceolate or hair-like, twisted scales 5–7 X 0.3–0.5 mm, tuberculiform aerophores at pinna bases; sterile pinnae (13–)18–30 pairs, free, straight to slightly falcate, 11–25(–36) X 1.8–3.2 cm, bases rounded to broadly cuneate, the largest stalked to 4 mm, apices longacuminate, margins entire to slightly undulate, serrulate at tips, recurved, abaxially with sparse to moderate tan scales 1–2 X 0.5–1 mm and twisted, hair-like or linear scales on costae, adaxially glabrous; veins simple or 1-forked, enlarged vein endings visible adaxially; fertile pinnae 8.5–18 X 0.2–0.5 cm, abaxially with sparse scales 1–3 mm on costae; indusia brown, lacerate at maturity, ca. 1 mm wide.A
Forma de vida
TerrestreA
Ejemplar revisado
(Related to the synonym Blechnum schiedeanum) Chis (Breedlove 22646, 31636, DS). Gro (Lorea 2103, IEB, MEXU). Hgo (Martínez 8, US). Méx (Hinton 5252, NY, UC, US). Oax (Mickel 6167, ENCB, NY, UC, 6546, NY, UC). Pue (Rzedowski 32426, ENCB, IEB; Ventura A. 404, ENCB, IEB, MEXU, NY). Ver (Ventura 89, ENCB, NY, 9366, ENCB, IEB, MEXU, NY).
Unverified, Doubtful, or Mistaken Reports. Jal (a specimen labelled as from Jalisco, Esperón M. 16722, UC, is mistakenly labelled, and actually from Edo. Veracruz).A
Unverified, Doubtful, or Mistaken Reports. Jal (a specimen labelled as from Jalisco, Esperón M. 16722, UC, is mistakenly labelled, and actually from Edo. Veracruz).A
Elevación
(350 –)750 – 1600(– 2300) mA
Ecología y Hábitat
Near streams.A
Tipo de vegetación
Bosque de neblina/mesófiloA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Blechnum schiedeanum (synonym) and B. falciforme are occasionally difficult to separate. The main distinguishing characters are the presence in B. falciforme of cartilaginous serrations along the whole pinna margins, dense scales 2–3 X 1–1.5 mm along the costae of the sterile and fertile pinnae, and appressed, twisted, hair-like scales 4–5 mm long on veins and laminae.
Blechnum varians, often regarded as a distinct species (e.g., by Smith, 1981, Mickel & Beitel, 1988; Moran in Davidse et al., 1995), is virtually identical to B. schiedeanum except that the stipes and rachises are dark purplish. It seems likely that pigmentation on the axes of this species is a response to increased exposure to light, and the pigmented variants seem to occur sporadically throughout the range of B. schiedeanum.
Blechnum cordatum (Desv.) Hieron., widespread and common in South America and with many synonyms, is very closely related to B. schiedeanum and perhaps not distinguishable. Monographic study is needed on this group of Blechnum before names can be applied with confidence.A