Curtisia dentata (commonly known as the Assegai tree or Cape lancewood, Afrikaans: Assegaai, Xhosa: Umgxina, Zulu: Umagunda) is a flowering tree from Southern Africa. It is the sole species in genus Curtisia, which was originally classed as a type of "dogwood" (Cornaceae), but is now placed in its own unique family Curtisiaceae.

It is increasingly popular as an ornamental tree for gardens, with dark glossy foliage and sprays of pure white berries. The bark of this tree is a very popular component of traditional African medicine, leading to overexploitation and a decline in the species in some areas of South Africa. The tree is protected in South Africa.