Jamesonia alstonii A.F.Tryon
Descripción
Rhizomes long-creeping, 1 mm diam.; rhizome hairs concolorous, brown, 1–1.5 mm long; fronds 15–40 cm long; stipes less than 1⁄6 the frond length, dark reddish brown, densely pubescent, hairs brownish, 2 mm long, to 3–4 mm long near the unrolling tip; blades linear, 1-pinnate, 0.4–1 cm wide; pinnae coriaceous, orbicular-cordate, 2.5–3 mm diam., stalks 0.5–0.8 mm long, adaxial surfaces with sparse hairs 1–1.5 mm long to glabrous with age, abaxial surfaces with abundant hairs 1–1.5 mm long; sori elongate along the veins, hidden by curled margins of the pinnae (modified indusia); indusia 0.8 mm wide with fimbriate margins; spores tan.A
Forma de vida
TerrestreA
Ejemplar revisado
Chis (Breedlove 24314, DS; Matuda 2864, S-234, NY, US). Oax (Mickel 5513, NY; Sharp & Webster 720A NY, TENN).
Unverified, Doubtful, or Mistaken Reports. Tab (reported by Magaña, 1992, but plant figured is Nephrolepis cordifolia, ‘Duffii’, escaped from cultivation).
A
Unverified, Doubtful, or Mistaken Reports. Tab (reported by Magaña, 1992, but plant figured is Nephrolepis cordifolia, ‘Duffii’, escaped from cultivation).
A
Elevación
2750 – 3600 mA
Ecología y Hábitat
Rocky soil by streams, flat meadows and steep slopes.A
Tipo de vegetación (notas)
With pines, junipers, and BuddleiaA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
This is the only species of Jamesonia in Mexico and grows at the most northern location in the genus (Sharp, Amer. Fern J. 61: 187. 1971). The Oaxaca locality is paramo-like in being high elevation, grassy, wet, and with cloud cover. Jamesonia alstonii grows with Huperzia crassa, another paramo plant reaching its northernmost locality there.A