Peristylus coeloceras Finet Rev. Gén. Bot. 13: 519. 1901.

凸孔阔蕊兰 tu kong kuo rui lan

Herminium coeloceras (Finet) Schlechter; H. tenianum Kraenzlin; H. unicorne Kraenzlin; Monorchis coeloceras O. Schwarz; M. teniana (Kraenzlin) O. Schwarz.

Plants slender, 6-35 cm tall. Tubers oblong-ovoid, 1-2 × 0.5-1 cm. Stem with 1 or 2 tubular sheaths at base, 1-3-leaved. Leaves clustered at base of stem, narrowly elliptic-lanceolate to oblong-elliptic, 2-10 × 0.8-2 cm, apex obtuse or acute. Inflorescence 5-27 cm; peduncle cylindric, slender; sterile bracts 1-3, occasionally foliaceous, ovate-lanceolate, 4-32 mm; rachis 2-10 cm, subdensely to densely many flowered; floral bracts lanceolate, 4-6 mm, slightly longer than ovary, apex acuminate. Flowers horizontal, white or pale whitish green; ovary 4-5 mm including pedicel. Dorsal sepal broadly erect, ovate, concave, 2-2.2 × ca. 1.8 mm, 1-veined, apex obtuse; lateral sepals spreading, cuneate-ovate, ca. 2.3 × 1.5 mm, 1-veined, apex obtuse. Petals ovate, oblique, 2-2.2 × ca. 1.4 mm, slightly fleshy above middle, 3-veined, apex obtuse; lip spreading, cuneate, ca. 3 × 2 mm, 3-lobed toward apex; disk with a large, glabrous, subglobose callus near base; lateral lobes oblong-ovate, ca. 0.5 mm, apex obtuse; mid-lobe oblong-ovate, ca. 0.8 mm, apex obtuse; spur pendulous, globose-saccate, very small, ca. 1 mm, apex obtuse. Column ca. 0.8 mm; viscidia elliptic; rostellum with short arms. Fl. Jun-Aug.

Coniferous and broad-leaved mixed forests, thickets, alpine grasslands; 2000-3900 m. W Sichuan, E and SE Xizang, NE and NW Yunnan [N Myanmar].