Subfossil beetles from a Neolithic well in central Europe

Wells from the Neolithic period of Central Europe (Linear Pottery Culture) are valuable archives for archaeological investigations and allow for a new perspective on this culture. Wood, ceramics, bones, pollen and insect remains have been conserved in sediments still humid today. Six Neolithic wells (5500 – 5000 BC) were found in Saxony, Germany; that of Brodau near Leipzig (ca. 5200 BC; discovered in 2005) was investigated in this study. A total of 80 samples yielded 2388 arthropod fragments, mostly from Coleoptera (besides few others from Hymenoptera, Diptera and Araneae).

Coleoptera remains are mostly isolated elytra, pronota and head capsules; legs, mouthparts or sternites are sparse. Conventional identification keys are not applicable to the fragments because they require consideration of several body parts. The fragments are usually well preserved including cuticular surface structures and occasionally colouration or hairs. We based species identification on (1) examination of fragments including details of the cuticular surface and (2) comparison with identified specimens in the institute's Coleoptera collection, using SEM and light microscopy. This revealed many previously unknown species-distinguishing characters, mainly on elytra. Yet, identification remains ambiguous in taxa including several very similar species.

The beetle fragments were assigned to 20 families, 36 genera and 27 species. More than 60 % are Aphodiinae (Scarabaeidae) especially Aphodius varians, A. granarius and Pleurophorus caesus. Four synanthropic species were detected, including the oldest records for Tenebrio obscurus and Oryzaephilus surinamensis, both pests on cereals. Carabidae (ca. eight species), Ceutorhynchus (Curculionidae) and Platystethus (Staphylinidae) were also well represented.