Baukea Vatke is considered to be a synonym of Rhynchosia Lour., and a new name, Rhynchosia baukea Du Puy & Labat, is given for the replaced synonym Baukea insignis Vatke. R. chapelieri Baillon is lectotypified. Morphological characters support the description of new species and subspecies of Rhynchosia and Eriosema: Rhynchosia androyensis Du Puy & Labat from southern Madagascar, R. leandrii Du Puy & Labat from western Madagascar and the Comoros, R. versicolor Baker subsp. imerinensis Du Puy & Labat and Eriosema betsileense Du Puy & Labat from central Madagascar.