Xanthophyllum rectumXanthophyllum rectum is a tree in the family Polygalaceae. The specific epithet rectum is from the Latin meaning 'upright', referring to the inflorescences.DescriptionXanthophyllum rectum grows up to tall with a trunk diameter of up to. The smooth bark is pale grey. The dark brown fruits are round and measure up to in diameter.Distribution and habitatXanthophyllum rectum is endemic to Borneo and confined to Sarawak. Its habitats include kerangas and dipterocarp forests.