岩上珠 yan shang zhu

Ophiorrhiza nana Edgeworth, Trans. Linn. Soc. London 20: 60. 1846; Clarkella siamensis Craib; O. pellucida H. Léveillé.

Low herbs, to 10 cm tall; tubers ellipsoid-oblong, 1-1.5 cm, scaly; stems unbranched, subterete, glabrous to densely villosulous. Leaves opposite or sometimes only 1 leaf developing at basalmost node; petiole 0.5-5 cm, glabrous to puberulent; blade drying membranous or thinly papery, ovate to broadly ovate, 1-6 × 1-4 cm, both surfaces glabrous to puberulent or villosulous, base obtuse to cordulate and sometimes oblique, apex acute to rounded; secondary veins 4-8 pairs; stipules triangular to narrowly triangular, 0.2-0.5 mm. Inflorescence 0.8-3 cm, 3-25-flowered, villosulous to puberulent; bracts ovate to narrowly oblong, 0.5-12 mm; pedicels 1-3.5 mm. Calyx densely puberulent to villosulous; hypanthium portion 1-2 mm; lobes triangular to ovate, 1-3 mm, markedly unequal on an individual flower. Corolla outside villosulous to puberulent; tube 10-14 mm; lobes elliptic to suborbicular, ca. 3 mm, ciliolate. Fruit 7-8 mm, villosulous, with calyx limb becoming 2-4.5 mm with increase in size principally in growth of basal, unlobed portion. Fl. and fr. Aug.

On wet rocks, usually limestone; ca. 1400 m. Guangdong (Liannan), N Guangxi (Nandan), C Guizhou, N Yunnan [N India, N Myanmar, Thailand].