Petersianthus is a genus of woody plant in the Lecythidaceae family first described as a genus in 1865 under the name Petersia.

[3][4] This turned out to be an illegitimate homonym, meaning that it had already been used by someone else to refer to a very different plant.

[5][6] So the name of these species in the Lecythidaceae was changed to Petersianthus.

[7][8] It is native to the Philippines and to parts of Africa.

[1] The following two species belong to this genus, with the basionyms of both taxa belonging to what is known today as the family Combretaceae.