紫斑杜鹃 zi ban du juan

Rhododendron monosematum Hutchinson, Bot. Mag. 142: t. 8675. 1916; R. pachytrichum Franchet var. monosematum (Hutchinson) D. F. Chamberlain.

Abaxial leaf surface mostly glabrous, glandular-strigose only on prominent midrib. Corolla red or white.

Forests, Rhododendron thickets; 2000–3800 m. Sichuan, Yunnan.

It is almost certain that var. monosematum is a hybrid between Rhododendron strigillosum and R. pachytrichum. The plate accompanying the original description illustrates a plant that is very close to R. pachytrichum, with pale flowers but with a long-stipitate-glandular indumentum. These features may be seen in naturally occurring populations of var. monosematum on Emei Shan in Sichuan. Therefore, it may be better to treat this taxon as a variety of R. pachytrichum. Plants resembling the photograph in Fang (Sichuan Rhododendron of China, 83. 1986) also occur there and are assumed to be back crosses with R. strigillosum.