少花石斛 shao hua shi hu

Aporum jenkinsii Griffith; Callista jenkinsii (Griffith) Kuntze.

Stems erect or ascending, compressed cylindric, 10-37(-45) cm, 2-7 mm in diam., rigid, sometimes branched, with many nodes, internodes clavate, 1-2 cm, with longitudinal ribs, yellow when dry, glossy. Leaves distichous, recurved above middle, laterally compressed and subcylindric, ensiform, 1.7-3 × 0.1-0.4(or more) cm, thickly fleshy, base dilated into clasping sheaths, apex acute or obtuse. Inflorescences bearing flowers successively one at a time from bundle of bracts, lateral on old leafy stem, 2-4 mm; basal sheaths 3 or 4, large; floral bracts ovate, 1-2 mm, membranous. Pedicel and ovary 6-15 mm, slender. Flowers fragrant, spreading, thinly textured, white or pale yellow, adaxial surface of lip with yellow spots. Dorsal sepal ovate to oblong, 3.3-12 × 2.5-5 mm, 7-veined, slightly obtuse or acute; lateral sepals ovate-triangular, ca. as long as dorsal sepal, 3.5-8 mm wide, 7- or 8-veined, base very oblique, apex acute; mentum bent forward, 10-20 × ca. 10 mm. Petals narrowly oblong to oblong, ca. 12 × 3 mm, 3-veined, obtuse or acute; lip spatulate to obovate-triangular, 15-25 × 7-10 mm, front margin undulate, emarginate; central part of disk with 2(-4) thickened raised veins terminating below lip apex, densely papillose near apex. Column 1-3 mm, foot 1-2 cm.

On trees in open forests, on trunks of Podocarpus in forests; ca. 1500 m. S Yunnan (Jinghong) [NE India, Laos, Thailand, Vietnam].

P. Ormerod (pers. comm.) questions the identity of the Chinese material, which might prove to be different from true Dendrobium parciflorum.