1. Oreorchis micrantha Lindley, J. Proc. Linn. Soc., Bot. 3: 27. 1858.
狭叶山兰 xia ye shan lan
Oreorchis rolfei Duthie.
Plants 20-35 cm tall. Pseudobulbs ovoid or oblong, 1-1.3 × ca. 1 cm, several noded, persisting and often forming a tight chain of pseudobulbs connected by a short rhizome. Leaves 2, linear-lanceolate or narrowly lanceolate, plicate, 17-25 × 0.5-1.2 cm, gradually tapering at base into an indistinct petiole-like stalk 4-7 cm. Inflorescence 20-32 cm, with 2 or 3 tubular sheaths below middle; rachis 4-6 cm, subdensely 8-12-flowered; floral bracts ovate-lanceolate, 1.5-3 mm. Flowers white, lip white with red spots on mid-lobe; pedicel and ovary 6-9 mm. Sepals oblong-lanceolate, 5.5-6 × 1.5-2 mm, apex subacute; lateral sepals slightly falcate. Petals lanceolate or linear-lanceolate, slightly falcate, 5-5.5 × ca. 1.2 mm, apex shortly acuminate; lip suboblong-obovate, ca. 5 × 3 mm, 3-lobed near base, shortly clawed at base; lateral lobes sublinear, ca. 1.5 mm, apex acute; mid-lobe obovate or broadly obovate, ca. 3 × 2.5 mm, apical margin irregularly incised and slightly crisped, apex obtuse and sometimes emarginate; disk with a linear, longitudinally channeled callus between lateral lobes and extending almost midway along mid-lobe. Column slightly arcuate, ca. 2.5 mm, base slightly dilated. Capsule pendulous, ellipsoid, 10-12 × ca. 5 mm. Fl. Jun.
Forests; 1500-3000 m. E and S Taiwan, S and SE Xizang [Bhutan, NE India, Myanmar, Nepal].