广西石斛 guang xi shi hu

Dendrobium guangxiense S. J. Cheng & C. Z. Tang; D. mitriferum Averyanov (2000), not J. J. Smith (1910).

Stems erect, slender, to 60 cm, 2-3 mm in diam. Leaves oblong, 4-4.5 × 1-1.5 cm, leathery, base sheathing. Inflorescences on old leafless stems, 1-3-flowered. Pedicel and ovary ca. 2.5 cm. Flowers whitish to yellowish, tinted pink, lip pale yellow flushed purple at base, with a purple transverse mark, anther cap wholly bright purple. Dorsal sepal ovate-lanceolate, ca. 15 mm, 5-veined, acute; lateral sepals ca. 16 mm, ca. 13 mm wide at base, 5-veined, subacute. Petals lanceolate, ca. 14 × 6 mm, very thin textured, subacute; lip 3-lobed, ca. 12 mm, ca. 9 mm wide at middle, margins serrulate, minutely pubescent near base; lateral lobes orbicular, ca. 4 mm in diam.; mid-lobe similar to lateral lobes, broadly ovate, ca. 6 mm, apex acute; disk ca. 4 mm, with central, ± square, swollen callosity. Column short.

Lithophytic on rocks or epiphytic on trees; ca. 1500 m. Guangxi, Yunnan [Vietnam].