Early Eocene rodents (Mammalia) from the Eureka Sound Group of Ellesmere Island, Canada

Rodents are a minor element in the Early Eocene terrestrial fauna from the Eureka Sound Group of Ellesmere Island. Nevertheless, at least five taxa ca n be recognized, all members of the family Ischyromyidae. Two are paramyine s, of which one is described as Paramys hunti, sp. nov. Three of the rodent s are microparamyines, Microparamys bayi, sp. nov., and two species of the new genus Strathcona, S. minor, sp. nov., and S. major, sp. nov. The paramy ines are Holarctic in distribution in the Early Eocene, but the microparamy ines are known only from North America and Europe. The Arctic Microparamyin ae provide the first clearly documented case for an early Cenozoic mammalia n taxon having a North American origin and later dispersal into Europe acro ss a North Atlantic terrestrial biogeographic province.