展羽毛蕨 zhan yu mao jue

Nephrodium amboinense C. Presl var. evolutum C. B. Clarke & Baker, J. Linn. Soc., Bot. 24: 417. 1888 ["evoluta"]; Christella evoluta (C. B. Clarke & Baker) Holttum; Cyclosorus chingii Z. Y. Liu ex Ching & Z. Y. Liu; C. flaccidus Ching & Z. Y. Liu; Dryopteris evoluta (C. B. Clarke & Baker) C. Christensen; N. evolutum (C. B. Clarke & Baker) Beddome; Thelypteris evoluta (C. B. Clarke & Baker) Tagawa & K. Iwatsuki.

Plants 60-120 cm tall. Rhizomes shortly to long creeping, including stipe bases with dark brown lanceolate scales. Stipes 15-40 cm, dark stramineous; laminae 40-80 × 20-40 cm, bases abruptly narrowed, apices caudate with a large apical pinna; lateral pinnae 10-20 pairs, proximal 1-5 pairs abruptly shortened, proximal pair triangular-auriculate, ca. 3 × 2 cm or longer, reflexed, sometimes hastate; middle pinnae lanceolate, 12-20 × (1.5-)2-4 cm, bases truncate to rounded-truncate, sessile or subsessile, lobed 1/5-1/3 toward costae, sometimes only crenate, apices long acuminate or caudate; segments 20-30 pairs per pinna on middle pinnae, ovate or oblong, 2-6 × 5-7 mm, obtuse at apices; veinlets 7-9 pairs per segment, proximal 1.5-3 pairs anastomosing, next 1-3 pairs running to sinus membrane. Laminae papery, grayish green when dried, subglabrous or glabrous on both surfaces (rarely shortly hairy). Sori orbicular, inframedial or medial; indusia glabrous or shortly hairy. Sporangia bearing large reddish orange spherical glands on stalks. Spores thickly cristate.

Wet places in dense forests; 300-1600 m. Chongqing, Guangxi, Guizhou, Hunan, Yunnan [India, Thailand].

There are several specimens of Cyclosorus evolutus with short hairs on the abaxial surface; but other characteristics are similar to the type, so no infraspecific name is given here.