Nematodes associated with the double‐spined bark beetleIps duplicatus(Coleoptera:Curculionidae) in centralEurope

Abstract

AbstractIps duplicatus(Sahlberg) is an important forest pest in centralEurope, but its nematode associates have seldom been studied. Therefore, nematodes associated withI. duplicatuswere determined at three localities in theCzechRepublic. The percentage of beetles with phoretic nematodes ranged from 18 to 65%.Micoletzkya buetschliiand other phoretic nematodes were found under elytra, on wings, and between body segments. The percentage of beetles with nematodes in the haemocoel ranged from 3 to 30%, and the nematodes includedContortylenchus diplogasterandParasitylenchuscf.aculeatus. Juveniles ofParasitorhabditis obtusa(Fuchs 1915) were found in the intestines of 0–16% of the beetles. The most abundant species inI. duplicatusgalleries wereP. obtusaandM. buetschlii. Cryptaphelenchussp.,Parasitaphelenchussp. and unidentified tylenchid juveniles also were found in the galleries. The percentage of beetles with nematodes was greater in the overwintering than in the offspring generation, and numbers of nematodes per gallery increased with gallery development.