Revision of the Malesian species of Dimorphocalyx (Euphorbiaceae)

Dimorphocalyx, a small genus ranging from Sri Lanka to Indomalesia to Australia, has eight species in Malesia, of which one is here raised from variety to species level and another, endemic in the N Moluccas, is newly described. Dimorphocalyx murinus and – tentatively – D. loheri are synonymised with D. denticulatus, and D. luzoniensis is synonymised with D. malayanus. Dimorphocalyx cumingii is regarded as a species of Trigonostemon. The differences between Dimorphocalyx, Ostodes, Paracroton (formerly Fahrenheitia), and Trigonostemon are discussed.