Additions to the begonia flora of sarawak, borneo, i: twelve new species and a new record

Twelve new species and one new record of Begonia (Begoniaceae) from Sarawak, Malaysia, are described. All species belong to Begonia sect. Petermannia. Three species are recorded from Totally Protected Areas, one species occurs both within and outside Totally Protected Areas, and eight species occur only outside Totally Protected Areas. Species descriptions, colour photographs and a distribution map are provided.