Lomaria euphlebia Kunze, Bot. Zeitung (Berlin) 6: 521. 1848; Lomariopsis triquetra (Wallich ex Mettenius) Ettingshausen; Plagiogyria attenuata Ching; P. chinensis Ching; P. christii Copeland; P. elongata R. D. Dixit & A. Das; P. euphlebia var. grandis (Copeland) De Vol; P. euphlebia var. triquetra (Wallich ex Mettenius) Ching; P. grandis Copeland; P. integripinna Ching; P. koidzumii Tagawa; P. maxima C. Christensen; P. triquetra Wallich ex Mettenius; Stenochlaena henryi Christ.

Stipes (7-)25-35(-70) cm on sterile fronds, (9-)40-75 cm on fertile fronds, distally ovate or tetragonal, rarely orbicular, in cross section; vascular bundle V-shaped to U-shaped; stipes and rachises glabrous to hairy, sometimes densely hairy; aerophores cushionlike. Sterile lamina pinnate, (11-)20-60(-135) × (7-)12-30(-40) cm, not glaucous, apically with a pinnalike segment; rachises abaxially usually semiterete; pinnae 7-25 pairs; proximal pinnae shortly stalked or rarely sessile, base usually equilateral, cuneate, rounded, or attenuate, not deflexed, not abbreviated or basal pair slightly shorter; middle pinnae shortly stalked or sessile, base cuneate or rounded; veins mostly simple to as many simple as forked. Fertile lamina pinnate, (9-)20-50(-80) × (3-)10-20(-33) cm; rachises abaxially semiterete, rarely flattened or grooved; pinnae 7-25 pairs, shortly stalked or sessile; proximal pinnae not abbreviated or basal pair slightly shorter. Paraphyses many, brown. Spores yellow or brown, with reddish tubercles. 2n = 260.

Forests; near sea level to 2500 m, usually 600-1500 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi, Sichuan, Taiwan, Yunnan, Zhejiang [Bhutan, India, Japan (including Ryukyu Islands), Korea, Myanmar, Nepal, Philippines, Vietnam].