• C. clarki
• C. gracilis
• C. milliensis
• C. trochuus

Cimolomys is a mammal genus from the Upper Cretaceous of North America. It was a member of the extinct order Multituberculata within the suborder Cimolodonta and family Cimolomyidae.

The genus Cimolomys was named by Marsh O.C. in 1889. It is also known as Allacodon (partly); Meniscoessus (partly); Ptilodus (partly); and Selenacodon (partly).

Species: Cimolomys clarki Sahni, 1972
Place: Texas & Wyoming (USA)
Age: Campanian-Maastrichtian, Upper Cretaceous. Possibly also New Jersey. Probably weighed about the same as a malnourished rat, 300 g.

Species: Cimolomys gracilis Marsh OC, 1889
Aka: Cimolomys digona Marsh, 1889; Meniscoessus brevis; Ptilodus gracilus (Osborn H.F. 1893); Selenacodon brevis (Marsh 1889)
Place: Montana, South Dakota, Wyoming & Sasakatchewan
Country: USA & Canada
Age: Maastrichtian, Upper Cretaceous. A rat-sized 415 g.

Species: Cimolomys milliensis (Eaton J.G. 1993a)
Place: Campanian (Upper Cretaceous) of Mill Creek, Utah (USA)

Species: Cimolomys trochuus (Lillegraven J.A. 1969)
Age: Maastrichtian (Upper Cretaceous) of North America
The holotype is in the collection of the University of Alberta.

References

• Marsh (1889), "Discovery of Cretaceous Mammalia". Am. J. Sci 3, 18 & 38: p.177-180.
• Kielan-Jaworowska Z & Hurum JH (2001), "Phylogeny and Systematics of multituberculate mammals". Paleontology 44, p.389-429.
• Much of this information has been derived from [1] MESOZOIC MAMMALS; "basal" Cimolodonta, Cimolomyidae, Boffiidae and Kogaionidae, an Internet directory.