麦穗石豆兰 mai sui shi dou lan

Rhizome stout, 4-5 mm in diam., rooting from base of pseudobulbs. Pseudobulbs 4-6 cm apart on rhizome, ovoid, usually 2-3 cm, base ca. 1.5 cm in diam., with a terminal leaf. Petiole 0.5-1 cm; leaf blade oblong, 8-30 × 1.5-3.4 cm, leathery or fleshy, base contracted into petiole, apex slightly retuse. Scape from base of pseudobulb, arching, 5-13 cm; raceme 3-6 cm, densely many flowered; peduncle with 4 or 5 large sheaths ca. 2 cm; floral bracts ovate-lanceolate, 5-6 mm, apex acute. Pedicel and ovary ca. 5 mm. Flowers yellowish green, with brown venation on sepals and petals and black spots on lip. Dorsal sepal ovate, ca. 6 × 3 mm, entire, acute; lateral sepals obliquely ovate-lanceolate, ca. 7.5 × 4.2 mm, abaxially slightly papillate, base adnate to column foot, their lower edges connate forming an ovoid sac, apex acute. Petals slightly obliquely triangular, ca. 2.5 × 1.8 mm, slightly decurrent to column foot, apex cuspidate; lip ca. 6 mm, fleshy, centrally grooved in basal half, apex obtuse, recurved, margin papillate, with 2 auricles on both basal sides; auricles falcate, ca. 1.3 × 0.4 mm, apex apiculate and irregularly toothed. Column yellow, subcylindric, ca. 2 mm; foot ca. 3 mm, with free part ca. 1.5 mm; stelidia subulate, ca. 1 mm; anther cap glabrous. Fl. Jun-Sep. 2n = 38.

Tree trunks in evergreen broad-leaved forests; 1000-2000 m. S and SW Yunnan [Thailand, Vietnam].