There are two species of Camptotheca, and the genus is endemic to China. They are medium-sized deciduous trees with papery, oblong-ovate leaves. The inflorescences are terminal or axillary heads with three bracts. The flowers are 5-merous and pale green, with the stamens mounted on a disc. The fruits are dry, contain a single seed and are winged. They are clustered in globose heads and have a persistent, apical disc. Until recently, only a single species of Camptotheca (C. acuminata) was recognised. However, in 1997 a second species (C. lowreyana S.Y. Li) was described, having ovate-cordate leaves with six to eight pairs of lateral veins (Qin & Chamlong 2005). This is grown at research institutions in Texas, but is not known to be cultivated as an ornamental. A dwarf selection named ‘Katie’ is said to be more cold- and drought-tolerant (Stephen F. Austin State University 2001). Camptotheca lowreyana has become an important element in research efforts into the anti-cancer drugs derived from camptothecins, currently obtained principally from C. acuminata.
Cornaceae (formerly Nyssaceae)