Elaphoglossum rufescens
Description
Rhizomes compact, horizontal, 2–3 mm diam.; rhizome scales linear-lanceolate, castaneous to blackish brown, lustrous, 5–6 mm long, with long slender apices, the hair-teeth deciduous or sparse; fronds clumped, (7–)16–30 X (0.8–)1.2–1.7 cm; phyllopodia distinct; stipes 1⁄3–1⁄2 the frond length, 0.7–0.9 mm diam., with scales sparse, appressed to spreading, brownish black, often orange distally, concolorous, 1–2 mm long; blades narrowly elliptic, narrowly cuneate at bases, acuminate at apices (rounded in juvenile plants); veins obscure, ca. 1 mm apart, at 70° angle to costa; hydathodes absent; blade scales lanceolate, mostly 1.5–2 mm long, short-toothed with the teeth ca. 1⁄2 the width of the scale body, scattered on the adaxial surfaces, orange-tan to white, abaxially abundant, imbricate, orange-tan, those of the costae 3–4 mm long, often dark-centered; fertile fronds shorter than (ca. 1⁄2 to nearly as long as) the sterile, the blades narrowly elliptic, 1–1.1 cm wide, bases broadly cuneate to rounded, apices acute, the costae scaly abaxially, the adaxial scales imbricate, absent among sporangia.A
A. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
Discussion
Elaphoglossum rufescens resembles E. paleaceum in the abundant blade scales but is distinct in the castaneous, sparsely toothed rhizome scales, slender stipes (0.7–0.9 mm diam. Instead of 1–1.5 mm), and longer stipes (1⁄3–1⁄2 the length of the frond instead of 1⁄5–1⁄4); the scales of the stipes and costae are dark-centered, not black-tipped, and the blade scales have short, stiff teeth (shorter than the width of the scale body instead of equal to, or longer than, the width). Elaphoglossum laxipes was distinguished by having longer, more slender stipes, but subsequent observations on Popocatepétl showed transitional forms to E. rufescens.B
B. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88
Distribution
México (Country) endemicC
Specimen
DF (Lyonnett 3469, US; Matuda 18794, US; Pringle 7088, MEXU; Purpus 1587, US; Rzedowski 34688, IEB). Jal (McVaugh 10044, MICH). Méx (Hinton 2750, US; Matuda 18794, MEXU; Rzedowski 23280, ENCB, NY). Pue (Balls 4469, US). D
D. Mickel, J. T. & Smith, A. R. 2004: The Pteridophytes of Mexico Vol. 88