34. Bulbophyllum rufinum H. G. Reichenbach, Xenia Orchid. 3: 44. 1881.
窄苞石豆兰 zhai bao shi dou lan
Rhizome stout, 5-6 mm in diam., with scalelike sheaths, rooting from base of pseudobulbs. Pseudobulbs ca. 8 cm apart on rhizome, pale yellow when dried, ovoid-conic, 2.5-4 cm, 1.5-2 cm in diam., with a terminal leaf. Petiole ca. 1 cm; leaf blade oblong, 11-20.5 × ca. 3 cm, fleshy or thickly leathery, base contracted into petiole, apex obtuse and slightly emarginate. Scape from base of pseudobulb, slightly arching, ca. 10 cm, often slender; raceme ca. 8 cm, sparsely many flowered; peduncle with several sheaths at base; floral bracts narrowly oblong-lanceolate, 7-20 mm, apex obtuse. Flowers yellow, thinly textured. Dorsal sepal ovate-lanceolate, ca. 6 × 2 mm, apex acuminate; lateral sepals ovate-lanceolate, ca. 9 × 2.2 mm, their lower edges connate to each other, upper edges incurved, apex acute. Petals obliquely ovate-lanceolate, ca. 2 × 0.9 mm, apex caudate; lip ligulate, ca. 3 × 1 mm, margins finely papillate, grooved at adaxial base, with 2 auricles on both basal sides, apex obtuse; auricles falcate, ca. 0.5 mm, apex acute. Column ca. 1.8 mm; stelidia subulate, ca. 1 mm; foot ca. 1.5 mm, with free part ca. 0.5 mm. Fl. Nov. 2n = 38.
Tree trunks in dense forests; 800-900 m. S Yunnan [Cambodia, Laos, Myanmar, Thailand, Vietnam].