Athyrium filix-femina var. angustum
Edinburgh New Philos. J. n.s. 19: 115. 1864.
Petiole (7–)15–55 cm; scales brown to dark brown, linear-lanceolate, 8(–10) × 2 mm. Blade elliptic, 2-pinnatifid to 2-pinnate, (20–)30–75 × (5–)10–35 cm, moderately narrowed proximally, broadest near or just below middle, apex acuminate. Pinnae short-stalked or sessile, oblong-lanceolate. Pinnules decurrent onto costal wing or sessile, linear to oblong, base unequally cuneate, apex obtuse to acute or in larger leaves acuminate, lobed halfway or more to costules. Rachis, costae, and costules glabrous or with pale glands. Sori straight, less frequently hooked at distal end or horseshoe-shaped; sporangial stalks bearing glandular hairs; indusia irregularly dentate, ± ciliate. Spores yellow or brown. 2n = 80.
Habitat: Moist woods, swamps, thickets
Elevation: 0–1100 m
Distribution
Greenland, Man., N.B., Nfld., N.S., Ont., P.E.I., Que., Sask., Conn., Del., Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Pa., R.I., S.Dak., Vt., Va., W.Va., Wis.
Discussion
Selected References
None.