Flora of North America species comparison

not proliferous.

not proliferous.

short-creeping, unbranched;

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

erect or ascending, rarely branched;

scales black throughout, linear-lanceolate, 2–3 × 0.2–0.4 mm, margin entire, apex attenuate.

monomorphic.

monomorphic.

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

indument of black filiform scales at base.

black or purplish black throughout, lustrous, 0.3–5 cm, 1/4–1/15 length of blade;

indument of black filiform scales at base.

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

base gradually reduced;

apex gradually reduced to whiplike rooting tip.

linear or narrowly oblanceolate, 1-pinnate throughout, 6–22(–37) × 1–1.8(–2.3) cm, thin, glabrous;

base tapered;

apex acute, not rooting.

in (12–)20–40 pairs, oblong;

medial pinnae 6–9 × 3–4 mm;

base broadly cuneate or auriculate;

margins crenate-serrate;

apex obtuse.

in 15–40 pairs, oblong;

medial pinnae somewhat asymmetric, oblong, 4–10 × 2–4(–5) mm;

base acute, acroscopically enlarged;

margins serrate to crenate, lobed;

apex obtuse.

free, obscure.

free, evident.

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

3–6 pairs per pinna, on both basiscopic and acroscopic sides of pinnae.

64 per sporangium.

64 per sporangium.

purplish black throughout, lustrous, glabrous or nearly so.

black throughout, lustrous, glabrous.

= 144, 216.