Flora of North America species comparison

not proliferous.

not proliferous.

ascending or short-creeping, infrequently branched;

scales dark brown to blackish throughout, narrowly deltate, 2–4(–5) × 0.2–0.5 mm, margins entire or shallowly denticulate to serrulate.

erect, unbranched;

scales black throughout, linear-lanceolate, 4–5 × 0.2–0.6 mm, margins entire.

monomorphic.

monomorphic.

dark reddish brown proximally, often fading to green distally, lustrous, 2–20 cm, 2/3–2 times length of blade;

indument of black filiform scales and minute hairs.

black throughout, lustrous, 1.5–3(–5) cm, 1/4–1/10 length of blade;

indument of blackish brown, filiform scales.

deltate, 2–3-pinnate, 2.5–10 × 2–6.5 cm, thick, hairs dark, scattered, minute;

base truncate;

apex acute to acuminate, not rooting.

linear to narrowly oblanceolate, 1-pinnate throughout, 9–20(–30) × 1–2(–2.5) cm, thick, glabrous;

base gradually tapered;

apex acute, not rooting.

in 4–10 pairs, deltate to lanceolate;

most proximal (largest) pinnae 1.5–4 × 1–2.5 cm;

base obliquely obtuse;

segment margins coarsely incised;

apex acute.

in 20–40 pairs, oblong;

medial pinnae (5–)10–20 × (2–)3–5 mm;

base usually with an acroscopic auricle;

margins ± entire to shallowly crenate;

apex obtuse.

free, evident.

free, obscure.

1–numerous pairs per pinna [1–6 pairs per segment], on both basiscopic and acroscopic sides.

2–5 pairs per pinna, on both basiscopic and acroscopic sides, often confluent with age.

64 per sporangium.

32 per sporangium.

greenish throughout or sometimes reddish brown proximally, lustrous, sparsely pubescent.

black throughout, lustrous, glabrous.

= 2n = 108 (apogamous).

= 144.