Flora of North America species comparison

not proliferous.

proliferous.

short-creeping, often branched;

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

erect, unbranched;

scales blackish throughout, linear to narrowly triangular, 0.9–1.3 × 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.

brownish black, 0.5–3(–5) cm, 1/9–1/7 length of blade;

indument of blackish, linear-lanceolate 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.

narrowly lanceolate, 2–3-pinnate, (4–)10–20(–)30 × 1–3(–5) cm, thin, glabrous;

base tapered somewhat;

apex formed by gradual reduction, not rooting.

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 (8–)12–16(–22) pairs, oblong;

medial pinnae 0.5–2.5 × 3–10 mm;

base cuneate;

apex obtuse.

free, evident.

free, evident, 1 per segment.

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

1 per segment.

64 per sporangium.

64 per sporangium.

reddish brown throughout, lustrous, glabrous or nearly so.

blackish brown, dull, essentially glabrous.

of 1–5 segments;

segments oblanceolate, 2–3 × 1–2 mm, entire;

apex mostly round.

= 72, 144.

= 144.