沼泽蕨 zhao ze jue

Plants 35-65 cm tall. Rhizomes long creeping, black, glabrous or with sparse reddish brown, ovate-lanceolate scales. Fronds approximate; stipes 20-40 cm, bases black, distally dark stramineous, polished, usually glabrous, or white pubescent when young; laminae lanceolate, 22-28 × 6-9 cm or sometimes slightly wider, bases almost tapering, pinnate-pinnatifid, apices shortly acuminate and pinnatifid; pinnae ca. 20 pairs, subopposite, flat- or obliquely spreading, usually slightly reflexed; proximal pair slightly shortened, middle pinnae lanceolate, 4-5 × 1-1.2 cm, bases truncate, pinnatifid nearly to costae, apices shortly acuminate; segments 5-7 × 3-5 mm, rounded-obtuse or obtuse-pointed at apices, fertile segments usually recurved to forming points along margin. Veins pinnate in segments, lateral veins 4-6 pairs, simple or forked and reaching margins, proximal pair arising from base of costa. Laminae papery, grass-green or yellowish green when dry, glabrous on both surfaces, rachises and costae grooved adaxially, raised abaxially, glabrous on both sides or with acicular long hairs abaxially. Sori orbicular, dorsifixed at middle of veinlets, located between costa and margins; indusia small, orbicular-reniform, membranous, deciduous when mature. Spores smooth on surfaces of exospore, perispores translucent, echinate. 2n = 70.

Meadows, reed marshes, wet shaded places in forests; 200-800 m. Hebei, Heilongjiang, Henan, N Jiangsu, Jilin, Nei Mongol, Shandong, Sichuan, Xinjiang [widely distributed in temperate regions of the N Hemisphere].

Lower Taxa

• Thelypteris palustris var. palustris
• Thelypteris palustris var. pubescens (G. Lawson) Fernald