Johnson, D.M. & Murray, N.A. (2018)
A revision of Xylopia L. (Annonaceae): the species of Tropical Africa Phytokeys 97 1-252
Description of the genus
Shrubs or trees. Inflorescences axillary, consisting of cymes or fascicles or solitary flowers. Sepals 3, ± united. Petals 6, free, in 2 whorls, thick, erect or spreading and often linear above. Stamens numerous, linear; filaments unites at base; anther-thecae transversely septate. Carpels free in fruit, dehiscent, ovoid-cylindric or flattened.