曲茎石斛 qu jing shi hu

?Dendrobium henanense J. L. Lu & L. X. Gao.

Stems cylindric, slightly upcurved, 6-11 cm, 2-3 mm in diam., unbranched, with several nodes, internodes 1-1.5 cm, pale brownish yellow when dry. Leaves 2-4, alternate on upper part of stem, oblong-lanceolate, ca. 3 × 0.7-1(or more) cm, subleathery, base decurrent into clasping sheaths, apex obtuse and slightly hooked. Inflorescences on old stems after leaves have fallen, 1- or 2-flowered; peduncle 1-2 cm, ca. 1 mm in diam.; basal sheaths 3 or 4, 2-4 mm, membranous; floral bracts pale white, ovate-triangular, ca. 3 mm, apex acute. Pedicel and ovary yellowish green, tinged with pale purple, 3-4.5 cm. Flowers spreading; dorsal sepal yellowish green abaxially, upper part slightly tinged with pale purple; lateral sepals yellowish green, upper distal margins tinged with pale purple, mentum yellowish green; petals: lower part yellowish green, upper part pale purple; lip pale yellow, front margin pale purple, margin purple below middle, disk with a large purple flabellate blotch at middle front part, callus yellow; column yellowish green, stelidia purple at base on outside, foot with 2 rounded purple spots, lower part yellowish green, apex purple, anther cap creamy white. Dorsal sepal oblong, ca. 28 mm, ca. 8 mm wide at middle, 5-veined, apex obtuse; lateral sepals obliquely ovate-lanceolate, ca. as long as dorsal sepal and broader, 5-veined, obtuse; mentum conic, ca. 8 × 10 mm, nearly rounded. Petals elliptic, ca. 25 mm, ca. 13 mm wide at middle, 5-veined, apex obtuse; lip broadly ovate, ca. 17 × 14 mm, adaxially densely pubescent, rear part with a saddle-shaped callus, base cuneate, margin inconspicuously 3-lobed, apex acute. Column ca. 3 mm, foot ca. 10 mm, sparsely covered with bifid hairs, upper part of hairs purple; column teeth 2, deltoid; anther cap subrhombic, ca. 2.5 mm, basal front margin with irregular teeth, apex deeply bilobed, lobes sharply toothed.

● Lithophytic on rocks in mountain valleys; 1200-2000 m. Henan, Hubei (Shennongjia), E Hunan (Heng Shan), SC Sichuan (Ganluo).