Description from Flora of China
Didymocarpus lanuginosus Wallich ex R. Brown, On Cyrtandreae 118. 1839; Corallodiscus bullatus (Craib) B. L. Burtt; C. cordatulus (Craib) B. L. Burtt; C. flabellatus (Craib) B. L. Burtt; C. flabellatus var. leiocalyx W. T. Wang; C. flabellatus var. luteus (Craib) K. Y. Pan; C. flabellatus var. puberulus K. Y. Pan; C. flabellatus var. sericeus (Craib) K. Y. Pan; C. labordei (Craib) B. L. Burtt; C. lineatus (Craib) B. L. Burtt; C. luteus (Craib) B. L. Burtt; C. mengtzeanus (Craib) B. L. Burtt; C. patens (Craib) B. L. Burtt; C. plicatus (Franchet) B. L. Burtt; C. plicatus var. lineatus (Craib) K. Y. Pan; C. sericeus (Craib) B. L. Burtt; C. taliensis (Craib) B. L. Burtt; Didissandra bullata Craib; D. cordatula Craib; D. flabellata Craib; D. labordei Craib; D. lanuginosa (Wallich ex R. Brown) C. B. Clarke; D. lineata Craib; D. lutea Craib; D. mengtzeana Craib; D. patens Craib; D. plicata Franchet; D. sericea Craib; D. taliensis Craib; D. taliensis f. robusta Craib.
Petiole to 4(-5.5) cm, adaxially glabrous to woolly, abaxially gray to brownish woolly to pannose; leaf blade broadly obovate to elliptic, rhombic, ovate, flabellate, or oblong, (0.5-) 1-5(-8) X (0.4-)0.8-3(-3.7) cm, flat to plicate or bullate, adaxially glabrous to densely villous, abaxially brownish pubescent to white to brownish woolly or puberulent to glabrous, margin subentire to crenulate, denticulate, or serrate, apex acute to rounded; lateral veins 3-5(or 6) on each side of midrib, adaxially flat to impressed, abaxially prominent to strongly prominent. Cymes (1-)4-15(-30)-flowered; peduncle (1-)3-17 cm, glabrescent to brownish woolly, glabrescent. Calyx 1.5-3.5 mm, outside glabrous to pubescent, rarely woolly. Corolla blue or purple to white or yellow, inside with or without spots on abaxial lip, (0.6-)0.8-1.4(-1.9) cm, outside glabrous to glabrescent; tube 5.5-10(-13) X 1.5-5.5 mm; adaxial lip lobes 0.6-2 mm; abaxial lip lobes 2-4(-6) mm. Stamens 2-6.5 mm; staminode 0.5-2.2 mm. Pistil glabrous; ovary 2-5 mm. Style 2-8 mm. Capsule narrowly oblong, 0.6-2.5 cm. Fl. Apr-Oct, fr. Jun-Dec.
As presently delimited, Corallodiscus lanuginosus includes seven taxa recognized in FRPS (Fl. Reipubl. Popularis Sin. 69: 233-245. 1990). Morphological variation in the present delimitation of C. lanuginosus includes indumentum (amount and type), leaf blade shape, size, margin, and texture, and flower number and size. The extent of this variation accounts for more than a few taxa previously described. However, in reexamining of all of these taxa, it became clear that the variation in all of these characters is continuous and is not correlated with the variation in other characters. For this reason it was impossible to clearly delimit previously recognized taxa. Thus, we recognize one, highly variable species, but further studies are needed to understand the variation.
The specimens from Xizang (Gyirong, Nyalam) and W Yunnan (Baoshan) differ from those of other areas in having the leaves entire or subentire, ovate or rarely obovate, flat or very
rarely slightly plicate, submembranous or thin papery, and glabrous or nearly so adaxially. They probably represent a subspecies of Corallodiscus lanuginosus or an independent
Rocky slopes, steep cliffs, forest margins, forests; 700-4300 m. N Guangdong, N Guangxi, Guizhou, Hebei, Henan, Hubei, NW Hunan, Shaanxi, Shanxi, Sichuan, Xizang, Yunnan [Bhutan, N India, Nepal, Sikkim, Thailand].