A taxonomic revision of Garcinia section Xanthochymus (Clusiaceae) in Thailand

section (Clusiaceae) is revised for Thailand with four native species, ., , , , and . All species are described with updated morphological descriptions, illustrations, and an identification key, together with notes on distributions, distribution maps, habitats and ecology, phenology, conservation assessments, etymology, vernacular names, uses, and specimens examined. Four taxa, , var. , and , are synonymized under , and two taxa, var. and , are newly synonymized under . Nine names are lectotypified: and its associated synonyms ( and ), and its associated synonyms ( , var. , and ), , and . All species have a conservation assessment of Least Concern (LC). The fruits of all species are edible and have a sour or sweet-sour taste.