Abstract
BACKGROUND: The genus Phytodietus Gravenhorst, 1829 is a species rich group of ichneumonid parasitoid wasps. It is represented in all zoogeographical regions, but knowledge of Phytodietus species in the Oriental region is patchy and restricted to some countries. NEW INFORMATION: Here the genus Phytodietus is recorded from Thailand for the first time based on three species. Diagnosis and illustrations of P. longicauda (Uchida, 1931), P. pitambari Kaur et Jonathan, 1979 and P. spinipes (Cameron, 1905) are given. Furthermore, known distributional and biological data of the species are summarised and an identification key to the species is provided.