禾杆紫柄蕨 he gan zi bing jue

Nephrodium microstegium Hooker, Sp. Fil. 1: 119. 1862; Lastrea microstegia (Hooker) Beddome; Pseudophegopteris pallida (Ching) Ching; Thelypteris brunnea (Handel-Mazzetti) Ching var. pallida Ching.

Plants 90-120 cm tall. Rhizome long creeping, with sparse, appressed, brownish, broadly lanceolate scales. Fronds remote; stipe stramineous, occasionally brown-stramineous, 30-40 cm, base with sparse brownish lanceolate scales, distally glabrous; lamina 60-80 × 20-30 cm, tapering proximally, pinnate-pinnatifid, pinnatifid and acuminate at apex; pinnae 20-25 pairs, subopposite, obliquely spreading or spreading, sessile, proximal pinnae linear-lanceolate, 10-15 × 2-3 cm, bases truncate, apices acute, proximal 2 or 3 pairs sometimes slightly shortened, 7-10 cm, pinnatifid nearly to costae; segments ca. 25 pairs per pinna, opposite, spreading, basal pair of segments same shape and size as more distal ones, oblong, 1-1.5 × ca. 0.5 cm, coarsely dentate or entire along margins, sparsely ciliate, obtuse or truncate at apices. Veins visible abaxially, lateral veins forked, 6 or 7 pairs per segment, basal pair arising from above base of costules. Laminae thinly herbaceous, drying greenish, both surfaces with short hairs along costae and veins, hairs denser adaxially, rachises stramineous, adaxially densely hirsute along groove. Sori orbicular to slightly oblong, borne at middle of acroscopic vein of lateral vein pair. Sporangia glabrous.

Evergreen broad-leaved forests; 2300-2400 m. Chongqing (Nanchuan), C Sichuan, S and SE Xizang, NW and SE Yunnan [NE India].

Pseudophegopteris microstegia is very similar to P. pyrrhorhachis (and treated as a synonym of that by Holttum, 1969), differing mainly in the stramineous stipes and rachises and laminae abaxially glabrous except on rachises and costae. The purported differences need further study.