none Megaselia; LEPIDOPTERAN-HOSTS; Paranthrene tabaniformis; Records; BULGARIA-; Records from lepidopteran hosts Paranthrene tabaniformis; DIPTERAN-PARASITES; Megaselia; Records; HYMENOPTERAN-PARASITES; Parasite prevalence & new host records; BULGARIA-; Dipteran & hymenopteran parasite prevalence & new host records Apanteles iarbas; Bracon mediator; Bracon triangularis; Dolichomitus messor; Dolichomitus populneus; Eriborus terebrans; Pristomerus rufiabdominalis; Pristomerus vulnerator; Scambus detritus; LEPIDOPTERAN-HOSTS; Paranthrene tabaniformis; New host record for Bulgaria HYMENOPTERA-; LEPIDOPTERAN-HOSTS; Paranthrene tabaniformis; Prevalence including new host records; BULGARIA-; Prevalence including new host records from lepidopteran hosts Studies on the species and distribution of the parasitoids of the poplar clearwing moth (Paranthrene tabaniformis (Rottemburg)) in Bulgaria have been carried out in the period 1987-1994. As a result, 11 larval parasitoid species, new for the host in Bulgaria, have been established. Seven of them (Eriborus terebrans Grav., Eriborus sp., Pristomerus vulnerator Panz., Pristomerus rufiabdominalis Ucida, Dolichomitus populneus Ratz., Dolichumitus messor Grav. and Scambus detritus Holm.) belong to fam. Ichneumonidae, 3 (Apanteles iarbas Nixon, Bracon triangularis Ns. and Bracon mediator Ns.) to fam. Braconidae and one (Megaselia sp.) - to fam. Phoridae. Among the parasitoids Bracon mediator Ns. is new species in the Bulgarian fauna. Six other - Eriborus sp., P. rufiabdominalis, D. messor, S. detritus, B. triangularis and Megaselia sp. - are reported for the first time and are new for the parasitoid complex of P. tabaniformis in the world. B. mediator destroys the young larvae of the poplar clearwing moth, E. terebrans and B. triangularis are connected both with the young and with the mature caterpillars, and the rest species - only with the mature larvae. A. iarbas, E. terebrans and B. triangularis are distinguished for biggest number, distribution and role. Together with the other species they decrease the density of the pest population in its separate habitats with 5.3-41.4%.