New eurytomid parasitoids of bark beetles in pine plantations in Ihtimanska Sredna Gora Mountains, Bulgaria

Abstract

In 2020, five eurytomid species were found for first time on bark beetles in Pinus sylvestris plantations in Ihtimanska Sredna Gora Mountains in Bulgaria: Eurytoma afra Boheman, 1836, Eurytoma arctica Thomson, 1875, Eurytoma morio Boheman, 1836, Eurytoma sp.1 and Eurytoma sp.2. One of them, E. arctica is a new species for the Bulgarian fauna. The parasitoids were reared from stem and branch samples infested by Ips acuminatus, Pityogenes bistridentatus, Pityophthorus pityographus, Tomicus piniperda and T. minor. All host-parasitoid associations are new for Bulgaria. In parasitoid complex, the most abundant species was E. morio (75.9%), followed by E. arctica (13.8%), Eurytoma sp. (6.9%) and E. afra (3.4%). The parasitism of the hosts varied between 2.6% (E. afra on I. acuminatus, P. bistridentatus and P. pityographus) and 33.3% (E. morio on I. acuminatus).