矩唇石斛 ju chun shi hu

Callista linawiana (H. G. Reichenbach) Kuntze; Dendrobium alboviride Hayata.

Stems erect, cylindric, somewhat compressed, usually 25-30 cm, stout, 1-1.5 cm in diam., unbranched, lower part narrowed, with several nodes, internodes slightly obconic, 3-4 cm, longitudinally grooved, yellowish brown when dry. Leaves oblong, 4-7(-10) × 2-2.5 cm, leathery, base dilated into clasping sheaths, apex obtuse and unequally bilobed. Inflorescence from old leafless stems, 2-4-flowered; peduncle 7-8 mm; basal sheaths 2 or 3, tubular, short; floral bracts ovate, 3-4 mm, apex acute. Pedicel and ovary to 5 cm; ovary slightly arcuate. Flowers spreading, large, white, sometimes upper part purplish red; lip white, upper part purplish red, disk with purplish red stripes on each side at base, anther cap white. Dorsal sepal oblong, 22-35 × 7.5-9.5(or more) mm, 5-veined, slightly obtuse; lateral sepals ± obliquely oblong, ca. as large as dorsal sepal, 5-veined, base oblique, apex slightly obtuse; mentum narrowly conic, ca. 8 mm. Petals elliptic, 22-35 mm, much broader than sepals, shortly clawed, obtuse; lip broadly oblong, ca. as large as petals or slightly smaller, both sides embracing column below middle, adaxially densely pubescent, shortly clawed, both lateral margins denticulate below middle, front reflexed, obtuse. Column ca. 4 mm, foot ca. 8 mm; anther cap glabrous.

● Epiphytic on tree trunks in mountain forests; 400-1500 m. E Guangxi (Jinxiu), Taiwan.