Published online by Cambridge University Press: 13 June 2014
Two new species of Begonia (Begoniaceae), Begonia gambutensis Ardi & D.C.Thomas and Begonia siregarii Ardi & D.C.Thomas, are described from material collected on the Indonesian island of Sulawesi. Both species belong to Begonia section Petermannia. A key to the species in the provinces North Sulawesi and Gorontalo is provided.