Paleoentomology of Mongolia

The scientific value of insect fossils is very high. The first remains of insects were discovered during the third Asian expedition of the American Museum of Natural History (1923) to the Anda-Khuduk locality. To date, 112 localities, from the Permian to Neogene, have been found in Mongolia, including the world’s largest lagerstätten Böön Tsagaan and Shar Teg. Most of them are Jurassic and Lower Cretaceous localities; Jurassic localities are significantly less numerous than Lower Cretaceous ones, which account for more than half of all known localities. Paleoentomological surveys have been performed with a varying intensity by the Joint Soviet–Mongolian Paleontological Expedition (JSMPE) and Joint Russian–Mongolian Paleontological Expedition (JRMPE) since 1970. A total of 17 expedition trips have been carried out. As a result, several tens of thousands of insect remains representing 29 orders, 299 families, 695 genera, and 870 species were obtained. However, the systematic position of many forms, especially homopetrans, coleopterans, and dipterans, has not been described or often even identified. More than 300 works have been published on the fossil insects of Mongolia, but less than half of the collected material has been described. Along with the paleontological collections, considerable attention was paid to paleoecological observations. To understand the history of water bodies, detailed studying and description of the structure of sediments and their stratigraphy have been performed. It has been revealed that ecosystems of ancient water bodies differed significantly from what could be restored based on Recent analogues. A new scheme of stratigraphic relationships between Jurassic and Cretaceous localities is provided. The analysis of paleogegraphic distribution of insect remains showed that localities of western Mongolia belong to a different paleozoogeographic division than the rest of its territory, which is biotically similar to Transbaikalia and China.