Flora of North America species comparison

usually long-creeping, 1.5–2.5 mm diam.

creeping to erect, scaly at apex.

monomorphic, dying back in winter, mostly evenly spaced 1 cm or more (sun-gathering leaves in loose cluster), (25–)40–85 cm.

monomorphic or somewhat dimorphic [dimorphic].

straw-colored, 4–25 cm × 1–3 mm, at base with scales tan to reddish brown, ovate, glabrous.

in cross section with 2 crescent-shaped vascular bundles at base.

elliptic, 15–60 cm, proximal 4–10 pinna pairs gradually smaller toward base (smallest often less than 5 mm), blade tapering gradually to pinnatifid apex.

pinnate to pinnate-pinnatifid, rarely more than 2-pinnate [simple];

rachis grooved adaxially or not, grooves not continuous with grooves of next order.

deeply pinnatifid to within 1 mm of costa, 3–9(–13) × 1–2(–2.5) cm;

segments oblong to linear, somewhat oblique, entire to crenulate;

proximal pair of veins from adjacent segments meeting margin above sinus.

free or anastomosing, running to margin, areoles with or without included free veinlets.

round, supramedial;

indusia tan, often ciliate;

sporangia glabrous.

inframedial to supramedial, occasionally nearly marginal, round or oblong, rarely elongate along veins;

indusia reniform or sometimes absent.

bilateral, monolete [rarely globose-tetrahedral and trilete], usually with a prominent, crested, echinate, or reticulate perispore.

green, cordate, usually hairy or glandular;

antheridia 3-celled.

abaxially of moderately to densely set hairs to 1 mm on rachises, costae, and veins, glands lacking or yellowish to light orangish, mostly sessile on blade tissue;

blades adaxially often with hairs on veins.

of transparent, needlelike, hooked, septate, or stellate hairs, or rarely hairs lacking.

= 54.