Beavers first appear in Asia, where fossil remains date back to the Eocene (33-36 million years ago). The most widespread Pleistocene giant beaver fossils were Siberian beavers – Trogontherium cuvieri and the North American beaver – Castoroides ohioensis. According to recent research, the oldest beavers in the Republic of Moldova are known from the deposits of Sarmatian (11.5 million years) – Steneofiber aff. depereti Mayeri, Chalicomys jaegeri (Kaup), Palaeomys castoroides Kaup, Trogontherium minutum minutum Franzet et Storch., T. minutum rhenanum Franzet et Storch. and Monosaulax cainarensis Lungu. In the Meotian (8.7-5.0 million years) only two species were recorded – Trogontherium minutum rhenanum Franzet et Storch. and Castor aff. praefiber Deperet. et Lungu.