Pellaea intermedia

Mettenius ex Kuhn

Linnaea 38: 84. 1869.

Illustrated
Synonyms: Pellaea intermedia var. pubescens Mettenius ex Kuhn
Treatment appears in FNA Volume 2.

Stems creeping, horizontal, slender, 2–4 mm diam.; scales mostly bicolored, narrowly lanceolate, largest scales 0.3–0.8 mm wide, centers black, thick, margins brown, thin, irregularly dentate. Leaves monomorphic, widely scattered along stem, 12–50 cm; croziers pubescent and bearing a few scales. Petiole straw-colored, tan, or gray, not lustrous, rounded or slightly flattened adaxially, without prominent articulation lines. Blade ovate to elongate-deltate, usually 2-pinnate proximally, 4–20 cm wide; rachis tan throughout, straight to slightly flexuous, rounded or flattened adaxially, ± pubescent. Pinnae perpendicular to rachis or slightly ascending, not decurrent on rachis, usually with 7–21 ultimate segments; costae straight to slightly flexuous, 20–100 mm, longer than ultimate segments. Ultimate segments ovate to elliptic, 5–15 mm, leathery, glabrous or usually puberulent abaxially; margins recurved on fertile segments, usually covering less than 1/2 abaxial surface, borders whitish, nearly entire; apex obtuse to slightly mucronate. Veins of ultimate segments obscure. Sporangia short-stalked, containing 32 spores, not intermixed with farina-producing glands. n = 2n = 87, 116, apogamous.


Phenology: Sporulating summer–fall.
Habitat: Rocky slopes and ledges, on a variety of substrates, including limestone and granite
Elevation: 300–2400 m

Distribution

V2 567-distribution-map.gif

Ariz., N.Mex., Tex., n Mexico

Discussion

Plants of Pellaea intermedia in the flora are apogamous triploids and tetraploids; a sexual diploid cytotype has been found near Saltillo, Mexico (A. F. Tryon 1968). Given the high degree of morphologic similarity among the three cytotypes, the North American polyploids probably were derived from the Mexican diploid through autopolyploidy.

Selected References

None.

Lower Taxa

None.

"thick" is not a number.

... more about "Pellaea intermedia"
Michael D. Windham +
Mettenius ex Kuhn +
cordate +, truncate +  and rounded +
glabrous +  and pubescent +
ovate +  and elongate-deltate +
4cm;20cm +
straight;slightly flexuous +
Ariz. +, N.Mex. +, Tex. +  and n Mexico +
300–2400 m +
yellow +  and white +
obcordate;reniform +
Rocky slopes and ledges, on a variety of substrates, including limestone and granite +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
monomorphic +
recurved +  and reflexed +
noncircinate +  and circinate +
12 cm120 mm <br />0.12 m <br /> (50 cm500 mm <br />0.5 m <br />) +
entire +, erose +  and dentate +
gray;tan;gray;tan;straw-colored +
pubescent +  and glabrous +
flattened +  and rounded +
Sporulating summer–fall. +
perpendicular +
straight +  and slightly flexuous +
not decurrent +, flattened +  and rounded +
persistent +
lanceolate +
Illustrated +
brown +  and tan +
cristate +  and tetrahedral-globose +
dark colored +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
slender +
Pellaea intermedia var. pubescens +
Pellaea intermedia +
species +
puberulent;glabrous +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
crescent--shaped +  and roundish +
branched +  and anastomosing +