The Microgastrinae genus Philoplitis Nixon is revised and four new species are described: P. keralensis sp. n. and P. trifoveatus sp. n. authored by Ranjith & Fernandez-Triana, and P. dzangasangha sp. n. and P. margalla sp. n. authored by Fernandez-Triana & Ranjith. A key to all nine known species is provided. Philoplitis adustipalpus Ahmad is redescribed and illustrated. Additional specimen records are presented, and the diagnostic value of some morphological characters previously used is discussed. Based on the very few specimens available for study in collections, Philoplitis seems to be restricted to the Old World tropics (Afrotropical and Oriental regions), with most known species found in the Oriental region. The first DNA barcodes for the genus are presented. No host data is currently available, but for one species a mass of five wasp cocoons was found and is illustrated for the first time.