Seorsumuscardinus, a genus of European dormice identified by fossils, lived around 17 million years ago during the early Miocene. Fossils from one species, S. alpinus, have been taken from rock strata in Oberdorf am Hochegg in Austria, Karydia in Greece, and Tägernaustrasse in Switzerland. A second species, S. bolligeri, was found at a single site in Affalterbach, Germany. Identified from many isolated teeth, both species were medium-sized dormice, with flat teeth characterized by long transverse crests coupled with shorter ones. Seorsumuscardinus may be related to Muscardinus, the genus of the living hazel dormouse, which appears in the fossil record at about the same time, and the older Glirudinus. Because the two known species lived at different times, the paleontologist Jerome Prieto has suggested that the genus may be useful for biostratigraphy, the use of fossils to determine the age of deposits. (Full article...)