Abstract
Summary A new species of Wrightia (Apocynaceae) from Vietnam, Wrightia vietnamensis Hazell & D.J.Middleton, is described and illustrated. Seed was collected on a Vietnamese led international collaborative expedition and grown on in the Temperate House at the Royal Botanic Gardens, Kew. When it matured and flowered, it was found to be an undescribed species. The species is currently only known from one karst limestone locality. This restricted distribution conforms to regional patterns of speciation and endemism in the genus whereby species restricted to karst limestone have very restricted distributions and those found on other soil types have wider distributions.