Flora of North America species comparison

not proliferous.

not proliferous.

short-creeping, often branched;

scales black throughout or with brown borders, lanceolate, 2–5 × 0.2–0.5 mm, margins entire to denticulate.

short-creeping, unbranched;

scales black with lighter margins, linear-lanceolate, 1.5–3 × 0.1–0.4 mm, margins entire.

monomorphic.

monomorphic.

reddish brown or blackish brown throughout, lustrous, 1–4(–7) cm, 1/6–1/4 length of blade;

indument absent or of black, linear-lanceolate or filiform scales at base.

purplish black, lustrous, 0.5–3 cm, 1/3–1/20 length of blade;

indument of black filiform scales at base.

linear, 1-pinnate, 3–22 × 0.5–1.5 cm, thin, glabrous or sparsely pubescent;

base gradually tapered;

apex narrowly acute, not rooting.

linear, 1-pinnate throughout, 7–17.5 × 0.9–1.8 cm, thick, glabrous;

base gradually reduced;

apex gradually reduced to whiplike rooting tip.

in 15–35 pairs, oblong to oval;

medial pinnae 2.5–8 × 2.5–4 mm;

base broadly cuneate, with or without low, rounded acroscopic auricle;

margins shallowly crenate to serrate or ± entire;

apex obtuse.

in (12–)20–40 pairs, oblong;

medial pinnae 6–9 × 3–4 mm;

base broadly cuneate or auriculate;

margins crenate-serrate;

apex obtuse.

free, evident.

free, obscure.

2–4 pairs per pinna, on both basiscopic and acroscopic sides.

3–7 pairs per pinna, on both basiscopic and acroscopic sides.

64 per sporangium.

64 per sporangium.

reddish brown throughout, lustrous, glabrous or nearly so.

purplish black throughout, lustrous, glabrous or nearly so.

= 72, 144.