Elaphoglossum glaucum
Description
Rhizomes short-creeping, ca. 5 mm diam.; rhizome scales linear-deltate, often hair-like most of their length, lustrous dark reddish brown to nearly black, to 17 mm long, entire; fronds clumped or a few mm apart, 13–62 X 1.7–3.8 cm; phyllopodia distinct; stipes 1⁄2–3⁄5 the frond length, glabrous; blades narrowly elliptic to oblanceolate, coriaceous, apices acute to obtuse or rounded, bases cuneate; veins obscure, free, curved, simple or once-forked, 1–1.5 mm apart, at ca. 70° angle to costa; hydathodes absent; blade surfaces glabrous to sparsely beset with minute, linear, hastate scales to 1–2 mm long; fertile fronds slightly shorter to somewhat longer than the sterile, but otherwise nearly equal in blade size and shape.A
A. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
Discussion
This species is most easily distinguished by the obtuse to rounded blade tips and the dark rhizome scales. Elaphoglossum guatemalense may sometimes have obtuse blades but has shorter, broader, darker rhizome scales and consistently has more slender rhizomes and minute stellate trichomidia on the abaxial blade surfaces. Elaphoglossum sartorii has orange or brownish rhizome scales, and its blades are acute to acuminate. The type has golden rhizome scales in contrast to the dark maroon scales typical of most specimens. Specimens from Orizaba at NY have castaneous scales and material from Jalisco, Guerrero, and Michoacán have golden scales, so apparently scale color is variable in the northern part of the range. Material in the southern part of the range (Chiapas to Honduras) has narrower, more bristle-like rhizome scales.B
B. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
Specimen
Chis (Breedlove 22731, NY). Gro (Rzedowski 23684, NY). Hgo (Moore 5307, UC, US). Jal (McVaugh 23106, MICH). Méx (Hinton 8997, NY). Mich (Hinton 15372, NY). Mor (Herrera s.n., MEXU). Nay (Kral 2566, ENCB). Oax (Mickel 4670, NY). Pue (Pringle 10836, US). Qro (Díaz B. 4979, IEB). Ver (Valdivia Q. 2212, IEB, XAL).
D
D. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
D