A new species of Astrotrichilia (Harms) J.-F. Leroy ex T. D. Penn. & Styles (Meliaceae, Melioideae) from seasonally dry forests in northern Madagascar is described. The new species is most similar to A. asterotricha (Radlk.) Cheek, but differs in a number of vegetative characters and has a distinct geographical distribution. A previous study of the new species has shown it to possess secondary compounds with antiproliferative properties towards ovarian cancer cells, highlighting the urgent need for its conservation. Images, a distribution map, and a preliminary assessment of risk extinction using the IUCN Red List Criteria are provided for the new species.