New Data on the Distribution of Southern Forests for the West Siberian Plain during the Late Pleistocene: A Paleoentomological Approach

Subfossil remains of insects and branchiopod crustaceans (Cladocera Notostraca) found in three late Pleistocene deposits the Novosibirsk region vicinity village Suzun have been described. The calibrated radiocarbon dates for these were 24,893–25,966 cal BP (Suzun-1), 20,379–20,699 (Suzun-2), 27,693–28,126 (Nizhny Suzun), which correspond to onset marine isotope stage 2 (MIS 2). insect assemblages are mainly represented by Coleoptera, noteworthy high taxonomic ecological diversity. At least 194 beetle species from 21 families altogether. Of them, 74 Western Siberia first time. All similar composition beetles; Carabidae Curculionidae prevailed everywhere. was dominated steppe tundra-steppe species; aquatic riparian groups also well represented. Cladoceran notostracan taxa revealed Suzun-1 Suzun-2 characteristic recent steppes rather than forest zone Siberia. studied entomocomplexes congruent with periglacial “Otiorhynchus-type” fauna that inhabited southern part West Siberian Plain at end had no close contemporary analogues. Cold dry conditions, as prevailing open landscapes type, reconstructed conditions this fauna. same time, a distinctive feature, namely proportion associated both coniferous deciduous trees. According data, beginning MIS Upper Ob region, spruce forests participation small-leaved (birch) present. They probably confined river valleys not widely distributed.