On the basis of previously documented genetic evidence, which correlates with morphological traits and a well-defined biogeographic pattern of distribution, Hilairanthus Tiegh. is recognized and reinstated as a genus of mangrove segregated from Avicennia (Acanthaceae). The genus is lectotypified, and the following combinations are formally proposed for Hilairanthus germinans, H. bicolor, and H. schaueriana.