A new species is described in Tetrapetalum, a small genus of which two
species have been known. Although Van Heusden (1992) stated that Tetr
apetalum differs from Cyathostemma only in its dimerous flowers, Tetra
petalum seems to be more closely related with Uvaria than with Cyathos
temma, because of spreading petals and unlobed stigmas. A key to the t
hree species of Tetrapetalum is provided here.