see text The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. This subfamily is larger than all mammal families except the Cricetidae, and is larger than all mammal orders except the bats and the remainder of the rodents. As a result, it has been said that murines are in the process of taking over the world, and humans just came along in the middle of it.

Description

The Murinae are native to Africa, Europe, Asia, and Australia. They are the only terrestrial placental mammals native to Australia. They have also been introduced to all continents except Antarctica, and are serious pest animals. This is particularly true in island communities where they have contributed to the endangerment and extinction of many native animals.

Two prominent murine human commensals have become vital laboratory animals . The brown rat and house mouse are both used as medical subjects and are among a handful of animals where the full genome has been sequenced.

The murines have a distinctive molar pattern that involves three rows of cusps instead of two, the primitive pattern seen most frequently in muroid rodents.

Fossils

The first known appearance of the Murinae in the fossil record is about 14 million years ago with the fossil genus Antemus . Antemus is thought to derive directly from Potwarmus , which has a more primitive tooth pattern. Likewise, two genera, Progonomys and Karnimata are thought to derive directly from Antemus . Progonomys is thought to be the ancestor of Mus and relatives, while Karnimata is thought to lead to Rattus and relatives. All of these fossils are found in the well-preserved and easily dated Siwalik fossil beds of Pakistan. The transition from Potwarmus to Antemus to Progonomys and Karnimata is considered an excellent example of anagenic evolution.

Taxonomy

Most of the Murinae have been poorly studied. Some genera have been grouped, such as the hydromyine water rats, conilurine or pseudomyine Australian mice, or the phloeomyine Southeast Asian forms. No tribal level taxonomy has been attempted for the complete subfamily. It appears as if genera from southeast asian islands and Australia may be early offshoots compared to mainland forms. The vlei rats in the genera Otomys and Parotomys are often placed in a separate subfamily, Otomyinae, but have been shown to be closely related to African murines in spite of their uniqueness.

Three genera, Uranomys , Lophuromys , and Acomys were once considered to be murines, but were found to be more closely related to gerbils through molecular phylogenetics. They have been assigned a new subfamily status, Deomyinae.

The Murinae have been divided into 121 genera and 519 species. The genera are listed alphabetically here.

List of Genera

• Subfamily Murinae - Old World rats and mice
  • Genus Abditomys
  • Genus Aethomys - bush rats
  • Genus Anisomys - powerful-toothed rat
  • Genus Anonymomys - Mindoro rat
  • Genus Apodemus - Old World field mice
  • Genus Apomys
  • Genus Archboldomys - Mount Isaro shrew rat
  • Genus Arvicanthis - unstriped grass mice
  • Genus Bandicota - bandicoot rats
  • Genus Batomys - Luzon and Mindanao forest rats
  • Genus Berylmys - white-toothed rats
  • Genus Bullimus
  • Genus Bunomys
  • Genus Canariomys - giant Canary Islands rat
  • Genus Carpomys - Luzon rats
  • Genus Celaenomys
  • Genus Chiromyscus - Fea's tree rat
  • Genus Chiropodomys - pencil-tailed tree mice
  • Genus Chiruromys
  • Genus Chrotomys - Luzon striped rats
  • Genus Coccymys
  • Genus Colomys - African water rat
  • Genus Conilurus - rabbit rats
  • Genus Coryphomys
  • Genus Crateromys - cloudrunners
  • Genus Cremnomys
  • Genus Crossomys - earless water rat
  • Genus Crunomys - Philippine and Sulawesian shrew rats
  • Genus Dacnomys - Large-toothed giant rat
  • Genus Dasymys - shaggy swamp rat
  • Genus Dephomys - defua rats
  • Genus Desmomys
  • Genus Diomys - Manipur mouse
  • Genus Diplothrix
  • Genus Echiothrix - Sulawesian spiny rat
  • Genus Eropeplus - Sulawesian soft-furred rat
  • Genus Golunda - Indian bush rat
  • Genus Grammomys
  • Genus Hadromys - Manipur bush rat
  • Genus Haeromys - pygmy tree mice
  • Genus Hapalomys - marmoset rats
  • Genus Heimyscus
  • Genus Hybomys - hump-nosed mice
  • Genus Hydromys - water rats
  • Genus Hylomyscus - African wood mice
  • Genus Hyomys - white-eared rats
  • Genus Kadarsanomys
  • Genus Komodomys
  • Genus Lamottemys
  • Genus Leggadina
  • Genus Lemniscomys - striped grass mice
  • Genus Lenomys - trefoil-toothed rat
  • Genus Lenothrix - grey tree rat
  • Genus Leopoldamys - long-tailed giant rats
  • Genus Leporillus - Australian stick-nest rats
  • Genus Leptomys
  • Genus Limnomys
  • Genus Lorentzimys - New Guinea jumping mouse
  • Genus Macruromys - New Guinean rats
  • Genus Malacomys - big-eared swamp rats
  • Genus Mallomys - giant tree rats
  • Genus Malpaisomys - Canarian lava fields mouse
  • Genus Margaretamys - Margareta's rats
  • Genus Mastomys - multimammate rats
  • Genus Maxomys - rajah rats
  • Genus Mayermys - Shaw-Mayer's mouse
  • Genus Melasmothrix - lesser Sulawesian shrew rat
  • Genus Melomys - banana rats
  • Genus Mesembriomys - tree rats
  • Genus Microhydromys
  • Genus Micromys - Old World harvest mouse
  • Genus Millardia - Asian soft-furred rats
  • Genus Muriculus - stripe-backed mouse
  • Genus Mus - mice
  • Genus Mylomys - African groove-toothed rat
  • Genus Myomys
  • Genus Neohydromys
  • Genus Nesokia - short-tailed bandicoot rat
  • Genus Niviventer - white-bellied rats
  • Genus Notomys - Australian hopping mice
  • Genus Oenomys - rufous-nosed rats
  • Genus Otomys - groove-toothed or vlei rats
  • Genus Palawanomys - Palawan rat
  • Genus Papagomys - Flores giant rats
  • Genus Parahydromys - mountain water rat
  • Genus Paraleptomys
  • Genus Parotomys - whistling rats
  • Genus Paruromys - Sulawesian giant rat
  • Genus Paulamys
  • Genus Pelomys - groove-toothed creek rats
  • Genus Phloeomys - slender-tailed cloud rats
  • Genus Pithecheir - monkey-footed rats
  • Genus Pogonomelomys - Rummler's mosaic tailed rats
  • Genus Pogonomys - prehensile-tailed rats
  • Genus Praomys - African soft-furred rats
  • Genus Pseudohydromys - New Guinea false water rats
  • Genus Pseudomys - Australian native mice
  • Genus Rattus - rats
  • Genus Rhabdomys - four-striped grass mouse
  • Genus Rhynchomys - shrewlike rats
  • Genus Solomys - naked-tailed rats
  • Genus Spelaeomys
  • Genus Srilankamys - Ceylonese rats
  • Genus Stenocephalemys - Ethiopian narrow-headed rats
  • Genus Stenomys
  • Genus Stochomys - target rat
  • Genus Sundamys - giant Sunda rats
  • Genus Taeromys
  • Genus Tarsomys
  • Genus Tateomys - greater Sulawesian shrew rats
  • Genus Thallomys - acacia rats
  • Genus Thamnomys - thicket rats
  • Genus Tokudaia - Ryukyu spiny rats
  • Genus Tryphomys - Mearn's Luzon rat
  • Genus Uromys - giant naked-tailed rats
  • Genus Vandeleuria - long-tailed climbing mice
  • Genus Vernaya - Vernay's climbing mouse
  • Genus Xenuromys - white-tailed New Guinea rat
  • Genus Xeromys - false water rat
  • Genus Zelotomys - stink mice
  • Genus Zyzomys - thick-tailed rats

Sources and further reading

• Chevret, P., C. Denys, J.-J. Jaeger, J. Michaux, and F.M. Catzeflis. 1993. Molecular evidence that the spiny mouse (Acomys ) is more closely related to gerbils (Gerbillinae) than to the true mice (Murinae). Proceedings of the National Academy of Sciences USA, 90:3433-3436.
• Jacobs, L.L. 1978. Fossil rodents (Rhizomyidae and Muridae) from Neogene Siwalik deposits, Pakistan. Bulletin of the Museum of Northern Arizona, 52: 1-103.
• Jansa, S.A. and M. Weksler. Phylogeny of muroid rodents: relationships within and among major lineages as determined by IRBP gene sequences. Molecular Phylogenetics and Evolution, 31:256-276.
• McKenna, M.C. and S. K. Bell. 1997. Classification of Mammals above the Species Level. Columbia University Press, New York.
• Michaux, J., A. Reyes, and F. Catzeflis. 2001. Evolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents. Molecular Biology and Evolution, 17:280-293.
• Musser, G.G. and M. D. Carleton. 1993. Family Muridae. Pp. 501-755 in Mammal Species of the World a Taxonomic and Geographic Reference. D.E. Wilson and D.M. Reeder eds. Smithsonian Institution Press, Washington D.C.
• Nowak, R.M. 1999. Walker's Mammals of the World, Vol. 2. Johns Hopkins University Press, London.
• Steppan, S.J., R.A. Adkins, and J. Anderson. 2004. Phylogeny and divergence date estimates of rapid radiations in muroid rodents based on multiple nuclear genes. Systematic Biology, 53:533-553.