Llavea Lag.
Descripción
Rhizomes stout, horizontal; rhizome scales mostly black, to bright yellow at stipe bases; fronds hemidimorphic, 2–3-pinnate, glabrous; veins free; sterile segments ovate with truncate to narrowly cuneate bases, 8–12 mm wide; blades fertile in distal third, fertile segments constricted, linear, 1.5–2 mm wide, margins inrolled, covering the sori, those slightly elongate along the veins; indusia modified, glandular hairs on inside surface; spores tetrahedral-globose; x=29.A
Forma de vida
Epipétrica o TerrestreA
Distribución
México (país) Nativo y no endémicoA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Llavea is distinct by its hemidimorphic fronds, recurved margin on the fertile segments, elliptic sterile segments, and the large, black rhizome scales, bright yellow at stipe bases. Llavea is a monotypic genus. Copeland (1947) regarded it as a derivative of Pellaea, but Tryon & Tryon (1982) cited recent placement of Llavea near Cryptogramma and Onychium. Molecular evidence (Gastony & Rollo, 1995) has shown Llavea to be not at all close to the cheilanthoid ferns, but instead related to Coniogramme of Asia.A