Flora of North America species comparison

not proliferous.

erect, unbranched;

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

monomorphic.

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

indument of blackish brown, filiform scales.

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 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, obscure.

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

32 per sporangium.

black throughout, lustrous, glabrous.

= 2n = 108 (apogamous).