below to form a monophyletic group (that is, they share a common ancestor more recently than with any other group), and other groups now considered muroids should not be included in the Cricetidae. The cricetids thus currently include one fossil and five extant subfamilies, with about 112 living genera and 580 species: Arvicolinae — voles, lemmings, muskrat Cricetinae — hamsters Democricetodontinae † (fossil) Neotominae — North American rats and mice, including deer mice, pack rats, and grasshopper mice Sigmodontinae — New World rats and mice, predominantly South American, such as brucies Tylomyinae — New World climbing rats and relatives Eumys † (fossil) Wilsoneumys † (fossil) References Eisenberg, J.F.; Feaver, J. & Krebs, C.J. (1984): Cricetidae. In: : The Encyclopedia of Mammals: 640–655, 672–673. Facts on File, New York. Savage, R.J.G. & Long, M.R. (1986): Mammal Evolution: an illustrated guide. Facts on File, New York. External links Rodent families Extant Miocene first appearances Taxa named by Gotthelf Fischer von Waldheim