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No abstract

Arthropods moving on large horizontal branches of old oaks (Quercus robur L.) in seven oak woodlands, SW Finland, were studied using a new trap type. The most abundant groups included Formicidae (Hym.), Oribatida (Acari), Thysanoptera, Nematocera (Dipt.), Collembola, Auchenorrhyncha (Hom.), Coleoptera, Araneae, Psocoptera and Hemiptera. The last three groups showed the least intersite variation in numbers of individuals. About 120 abundant, rare and other interesting species of Diplopoda (4 species mentioned), Chilopoda (2), Araneae (19), Opiliones (4), Pseudoscorpionida (1), Oribatida (9), Psocoptera (9), Blattodea (1), Neuroptera (1), Homoptera (10), Heteroptera (13), Coleoptera (25), Lepidoptera (14) and Formicidae (6) are listed, and the new trap is described.

The saproxylic sap beetleGlischrochilus(Glischrochilus)quadripunctatus(Linnaeus, 1758), is associated with subcortical habitats of coniferous trees. This species is widely distributed across Europe and Siberia, and is the best known and largest European nitidulid species. A closely related cryptic species,G.(G.)tremulaesp. nov.has been discovered in a xerothermic area of SE Finland in association with old aspens. The two species exhibit a sympatric occurrence in SE Finland, on their respective host trees. We analyze the COI barcode region to compareG.(G.)quadripunctatus,G.(G.)tremulaesp. nov., andG. (Librodor) hortensis(Fourcroy, 1785). Morphological, ecological, and molecular data confirm the presence in SE Finland of twoGlischrochiluss.str. species. We provide a description of the new species. The newGlischrochilusapparently represents a relictual taxon associated with old hollow aspens, and should be considered a species with inherent conservation value within European saproxylic beetle communities.

Entomologica Fennica. Vol. 3:98. 31.VIII.1992