Diplazium errans Lorea-Hern. & A.R.Sm.

Primary tabs

Diplazium errans Lorea-Hern. & A.R.Sm.

Descripción

Rhizomes ascending to erect; rhizome scales concolorous, dark brown, lustrous, 0.5–1 X 0.3–0.5 mm, lanceolate, entire; fronds ca. 100 cm long; stipes pale gray-green or dark green, 34–40 cm X 2–3 mm, 1⁄3–2⁄5 the frond length, glabrous except for brown, dull scales at bases; blades thick-herbaceous to subcoriaceous, 1-pinnate, 52–66 X 17–22 cm, lanceate, apices pinnatifid, one or two buds developing in pinna axils on distal 1⁄4 of blades; rachises lacking hairs and scales, but with papillae <0.1 mm long in adaxially grooves; pinnae stalked 5–7 mm, falcate, inequilateral, 20–28 pairs per blade, largest pinnae (usually second or third pair) 11–15 X 1.7–2.5 cm, lanceolate, smallest pinnae 0.7–1.3 X 0.4–0.7 cm, elliptic or rhombic, bases cuneate basiscopically, slightly auriculate acroscopically, apices caudate-acuminate, margins shallowly lobed to undulate and with lobes faintly serrulate; veins free, main lateral veins from costae 4–6-branched (2–3 pairs), branches subabruptly curved and running toward pinna margins; indument absent on both sides of blades except for minute papillae <0.1 mm in adaxial costal grooves; sori along 1–3 acroscopic and also along 0–2 basiscopic veins of a vein group, with indusia 2.5–9.5 X 0.2–0.4 mm, entire.A

Forma de crecimiento

Hierba

Forma de vida

TerrestreA

Nutrición

Autotrófica

Ejemplar revisado

Known only from the type collection. Gro (Campos 1531, XAL, NY!, UC!).A

Distribución

México (país) EndémicoA

Elevación

1000 mA

Tipo de vegetación

Bosque de neblina/mesófilo, Bosque de pino-encinoA

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

This species is mostly closely related to D. werckleanum, which agrees in having 1-pinnate blades, shallowly lobed pinnae, and similar venation and soriation. However, D. werckleanum has at most 10 (usually 5–10) free pinna pairs per blade and lacks buds, while D. errans has more than 20 free pinna pairs per blade and bears buds in the axils of distal pinnae. Another related gemmiferous species in Mexico is D. vera-pax, but the latter has only 1–3 free pinna pairs. It seems unlikely that D. errans is a hybrid involving either D. werckleanum or D. vera-pax, because no other 1-pinnate Diplazium with inequilateral pinna bases, more than 20 pinna pairs, glabrous blades, and proliferous buds is known to occur in Mexico or Mesoamerica.
Diplazium errans is known only from the type collection; however, the species was not rare at the type locality, according to observations by the collector. Pine-oak forests at ca. 1000 meters on the western slopes of the Sierra Madre, where D. errans grows, are not common in Guerrero, having been mostly cut in farming and logging operations.
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]