Description from Flora of China
Alismorkis tricarinata (Lindley) Kuntze; Calanthe lamellata Hayata; C. megalopha Franchet; C. undulata Schlechter; Paracalanthe lamellata (Hayata) Kudô; P. megalopha (Franchet) Miyabe & Kudô; P. tricarinata (Lindley) Kudô.
Plants 35-50 cm tall. Rhizome inconspicuous. Pseudobulbs globose, ca. 2 cm in diam., with 3 sheaths. Leaves 3 or 4, basal, not well developed at anthesis, not deciduous; blade elliptic or obovate-lanceolate, 20-30 × 5-11 cm, abaxially densely puberulent, margin undulate, apex acute or acuminate; petiole-like base sheathing, forming a stout pseudostem 4-15 cm long and 1-2.5 cm in diam.; sheaths large, apex obtuse, lowest one ca. 2 cm, upper sheaths longer. Scape arising from leaf axil, erect, to 60 cm, to 1.5 cm in diam., stout, puberulent, with several to many ovate-lanceolate sterile bracts; rachis 3-20 cm, laxly few to many flowered; floral bracts persistent, ovate-lanceolate, 5-10 mm, membranous, glabrous. Flowers pale yellow, with reddish brown lip; pedicel and ovary 10-20 mm, puberulent. Sepals similar, oblong-lanceolate, 16-18 × 5-8 mm, abaxially sparsely puberulent at base, 5-8-veined, apex acuminate. Petals obovate-lanceolate, 11-15 × 3-5 mm, 3-veined, apex acute or subobtuse; lip adnate to base of column wings, reddish brown, 10-16 × 7-15 mm, spurless, 3-lobed; lateral lobes auriculate or nearly suborbicular, small, ca. 4 × 4-5 mm; mid-lobe reniform, 8-10 × 10-15 mm, margin strongly undulate, apex emarginate and mucronate in sinus; disk with 3-5 crested lamellae. Column ca. 6 mm, thick, ventrally sparsely puberulent; rostellum 2-lobed; anther cap beaked; pollinia narrowly obovoid-globose, ca. 2 mm, with conspicuous caudicles; viscidium elliptic, small, ca. 1 mm. Fl. May-Jun. 2n = 40, 42, 60.
Grassy slopes, forests; 1300-3500 m. S Gansu, Guizhou, Hubei, S Shaanxi, Sichuan, Taiwan, SE Xizang, Yunnan [Bhutan, NE India, Japan, Kashmir, Nepal].