Flora of North America species comparison

short-creeping;

scales dark reddish brown, concolored, margins entire.

short-creeping;

scales bicolored, centers dark reddish brown, margins pale tan, erose-ciliate.

arching, clustered, 20–37 cm.

arching or sometimes pendent, closely spaced, 20–110 cm.

1–2 mm diam., adaxially hispid, not glaucous.

1–3 mm diam., glabrous, occasionally glaucous.

lanceolate, pinnate or occasionally pseudopedate, 1-pinnate distally, 12–18 × 6.5–8 cm;

proximal pinnae 1–4-pinnate;

indument of light-colored, sparse, multicellular hairs;

rachis straight, densely hispid, not glaucous.

trowel-shaped, pinnate, 12–60 × 12–60 cm, gradually reduced distally, glabrous;

proximal pinnae 3-pinnate;

rachis straight, glabrous, not glaucous.

oblong to long-triangular, ca. 2 times as long as broad, progressively reduced toward apex of penultimate divisions;

basiscopic margin oblique;

acroscopic margin of fertile segments crenulate, sterile segments sharply denticulate;

apex obtuse or acute.

fan-shaped or rhombic, about as long as broad;

base cuneate;

apex rounded or acute, lobed, lobes separated by narrow incisions 0.5 mm wide.

transversely oblong to crescent-shaped, 0.5–2 mm, glabrous.

± round, 0.6–0.9 mm diam., covered with reddish brown, stiff, needlelike bristles.

mostly 40–60 µm diam.

mostly 40–58 µm diam. 2n = 60.

stalks 0.2–0.3 mm, dark color generally entering into segment base.

stalks 1–5 mm, with dark color ending abruptly at segment base, terminating in cupulelike swelling at base of segment (unlike any other species of Adiantum in the flora).