掌唇兰 zhang chun lan

Cleisostoma dawsonianum H. G. Reichenbach, Gard. Chron. 1868: 815. 1868; Sarothrochilus dawsonianus (H. G. Reichenbach) Schlechter; Trichoglottis dawsoniana (H. G. Reichenbach) H. G. Reichenbach.

Stems ascending, terete, to more than 50 cm, 6-7 mm in diam., rigid, sometimes branching, with many nodes, internodes 1.5-2.5 cm. Leaves many, distichous, narrowly oblong, 11-15 × 1.5-2 cm, obtuse and unequally bilobed. Inflorescence opposite to leaf, paniculate, to 45 cm, laxly many flowered; peduncle 3-4 mm in diam.; rachis yellowish green, slightly compressed or ± trigonous, narrowly winged; floral bracts ovate-triangular, 5-7 mm, obtuse. Flowers opening widely, fleshy, sepals and petals pale yellow, adaxially with chestnut transverse stripes, lip orange-yellow, disk with a central red band; pedicel and ovary 1.5-2 cm. Dorsal sepal subspatulate, ca. 15 × 5 mm, dorsally carinate, mucronate; lateral sepals slightly oblique, oblong, ca. 15 × 5 mm, rostrate. Petals spatulate, ca. 14 × 4 mm, retuse and shortly rostrate; lip ca. 7 mm, 5-lobed; basal lobes oblong, ca. 4.8 × 1.7 mm; lateral lobes narrowly oblong, ca. 4 × 1.5 mm, obtuse; apical lobes narrowly obovate, ca. 2.5 mm, thickly fleshy, obtuse and emarginate at apex; disk densely hirsute; spur conic, ca. 1 mm, thickly fleshy, with a broadly ovate-triangular appendage on its back wall. Column ca. 3 mm, stout, stelidia hirsute; stigma large, at base of column; anther cap subglobose, densely minutely papillate-hairy. Capsule narrowly ellipsoid, ca. 4 × 1 cm. Fl. May-Jul, fr. Sep-Oct. 2n = 38.

Epiphytic on tree trunks at forest margins; 500-800 m. S Yunnan [Laos, Myanmar, Thailand].