Description from Flora of China
Callista loddigesii (Rolfe) Kuntze; Dendrobium loddigesii var. album Tang & F. T. Wang.
Stems often pendulous, cylindric, 10-45 cm, slender, ca. 3 mm in diam., soft, sometimes branched, with many nodes, internodes 1.5-2 cm, golden yellow when dry. Leaves alternate along entire stem, ligulate, oblong-lanceolate, or slightly obliquely oblong, usually 2-4 × 1-1.3 cm, leathery, base sheathing, apex acute and slightly hooked; leaf sheath membranous, veins raised into a lattice when dry; sheath mouth often open when dry. Inflorescence lateral on upper part of old leafy stem, 1- or 2-flowered; peduncle 2-3 mm; basal sheaths 1 or 2, cupular, short, membranous; floral bracts ovate, ca. 2 mm, membranous, apex obtuse. Pedicel and ovary 2-3 cm. Flowers pale pink or purplish red, adaxial surface of lip golden yellow at center, pale purplish red on edge, column white, front lateral sides with red stripes, anther cap white. Dorsal sepal ovate-oblong, 17-20 × ca. 7 mm, 5-veined, apex acute; lateral sepals lanceolate, 17-20 × 6-7(or more) mm, 5-veined, base oblique, apex acute; mentum subglobose, ca. 5 mm. Petals elliptic, ca. as long as dorsal sepal, 8-9(or more) mm, 3-5-veined, margin entire, apex slightly obtuse; lip suborbicular, 17-20 mm in diam., both surfaces densely pubescent, margin shortly fimbriate, apex emarginate. Column ca. 4 mm; anther cap subconic, densely finely papillate-hairy, front margin irregularly dentate.
Epiphytic on tree trunks in mountain forests, lithophytic on rocks in forests; 400-1500 m. Guangdong (Hong Kong, Luofu Shan), Guangxi, SW Guizhou, Hainan (Baisha), S Yunnan (Mengla, Simao) [Laos, N Vietnam].