A new species of the bee genus Tetralonia subgenus Thygatina is described and figured from southern India. Tetralonia (Thygatina) macroceps, new species is particularly noteworthy for macrocephaly in males, among other characters. Previously the Oriental fauna of Thygatina was thought to consist of a single described species. Aside from T. (T.) fumida (Cockerell) and the new species proposed herein, the fauna also includes T. wickwari (Bingham), erroneously placed in Eucara (as a genus), and herein recognized as a species of Thygatina, which is thereby newly transferred to the genus Tetralonia (new combination). In addition, there remains at least one additional undescribed species, but owing to confusion surrounding the association of sexes for T. fumida and T. wickwari this material is left unnamed. The need for additional collecting in southern India and Sri Lanka is stressed in order to resolve this difficulty. Lectotypes and paralectotypes are designated for T. fumida and T. wickwari.