Flora of North America species comparison

not proliferous.

not proliferous.

erect, unbranched;

scales black with lighter margins, linear-lanceolate, 3–6 × 0.4–0.8 mm, margins entire.

erect, much branched to produce dense many-stemmed tufts or mats bearing numerous crowded leaves;

scales dark reddish brown to black throughout, narrowly deltate, 2–4 × 0.3–0.6 mm, margins entire.

monomorphic.

monomorphic.

reddish brown throughout, lustrous, 1–12(–20) cm, 1/3–1/10 length of blade;

indument of black filiform scales.

dark reddish brown proximally, fading to green distally, 2–13 cm, 2–5 times length of blade;

indument absent.

linear, 1-pinnate throughout, 5–25(–40) × 1–2.5(–3) cm, thick, glabrous;

base gradually tapered;

apex acute, not rooting.

linear, simple or more often 1-pinnate, 0.5–4 × 0.1–0.4 cm, occasionally wider when pinnae strongly diverge, leathery, glabrous;

base acute;

apex acute, not rooting at tip.

in 10–40 pairs, oblong to quadrangular, somewhat asymmetric;

medial pinnae 4–15 × 2–5 mm;

base rounded to cuneate;

margins crenulate or ± entire;

apex obtuse.

of pinnate leaves 2(–4), strongly ascending to give forked appearance, linear, (5–)10–30 × 0.75–3 mm;

base acute;

margins remotely lacerate;

apex acute.

free, obscure.

free, obscure.

1(–3) per pinna, only on basiscopic side.

usually 2+ per pinna, parallel to margins.

32 per sporangium.

64 per sporangium.

reddish brown throughout, lustrous, glabrous.

green, lustrous, glabrous.

= 2n = 108 (apogamous).

= 144.