Pellaea intermedia Mett.
ex Kuhn, (Latin: intermedius, that which is in between, = intermediate)
Local names: intermediate cliff-brake, creeping cliff-brake

Plant to 50 cm tall; rhizomes slender (less than 5 mm diam.), cord-like, longcreeping, the scales with 2 distinct colors, black in center with brown along margins; petioles straw-colored, tan, or gray, not shiny; leaf blades usually 2-pinnate below, 4–20 cm wide, monomorphic; rachis and costae pubescent with short hairs, or glabrescent; pinnae attached to rachis so that their tips point more or less straight out or slightly towards tip of leaf; ultimate leaf segments ovate to elliptic, apically obtuse to very slightly mucronate, leathery, essentially truncate at base, glabrous or puberulent on lower surfaces;
n =
2n = 87, 116 (Windham 1993c). Canyons, slopes, rocky areas; widespread in the Trans-Pecos and Upton (
Correll 13567, BRIT, TEXLL) and Val Verde (
Tharp 4286, TEX-LL, “Devil’s River, Del Rio”, which is well to the e of Pecos River) cos. in w Edwards Plateau; AZ, NM, and TX; also n Mexico. Sporulating Mar–Nov. [
P. intermedia var.
pubescens Mett. ex Kuhn] Windham (1993c) noted that members of this species in the U.S. are apogamous triploids and tertraploids. However, a sexual diploid population is known from Mexico (Tryon 1968) and Mickel and Smith (2004) suggested that “given the morpho-logical similarity among the three cytotypes” the polyploids probably arose through autopolyploidy.
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