Haplocoelum perrieri Capuron Gereaua is a monotypic genus of flowering plants belonging to the family Sapindaceae.

[2] Gereaua perrieri is a small or medium-sized tree which grows up to 10 meters tall.

[1] Gereaua perrieri is native to northern and eastern Madagascar, where it is found in Diana, Sava, Analanjirofo, Alaotra-Mangoro, Analamanga, Haute- Matsiatra, Vatovavy-Fitovinany, Atsimo-Atsinanana, and Anosy regions.

The species is subject to habitat loss from shifting cultivation, and its population is thought to be decreasing.

[4] The specific Latin epithet of perrieri is in honour of Joseph Marie Henry Alfred Perrier de la Bâthie (1873–1958), a French botanist who studied Madagascan plants.