Four new species of the genus Diolcogaster Ashmead, 1900 (Hymenoptera: Braconidae: Microgastrinae) from South East Asia with a key to the Indian species.

Four new species of the genus Diolcogaster Ashmead, 1900 (Hymenoptera: Braconidae: Microgastrinae) are described and illustrated: Diolcogaster andamanensis n. sp. from the Andaman Islands, and D. duocolor n. sp., D. longistria n. sp. and D. solitarium n. sp. from mainland India. The solitary larval parasitoid D. solitarium was reared from Gatesclarkeana sp. (Lepidoptera: Tortricidae). A new combination, Diolcogaster tomentosae (Wilkinson, 1930) n. comb., is proposed for the Indian species Protomicroplitis tomentosae (Wilkinson, 1930) along with its redescription and documentation of the gregarious cocoons associated with the pyralid (Epipaschiinae) host feeding on Terminalia cattappa L.