Bryceomys

Bryceomys
Scientific classification
Kingdom: Animalia Therapsida Class: Mammalia Order: Multituberculata Grade: Paracimexomys group Genus: Bryceomys
Species
B. fumoses   B. hadrosus   B. intermedius
Ref.

Bryceomys is an extinct mammal that lived during the Upper Cretaceous, and thus shared the world with dinosaurs. It was a member of the also extinct order of Multituberculata.
For those of a technical disposition, it's within the Suborder of Cimolodonta, and a member of the Paracimexomys group.

Genus: Bryceomys Eaton JG, 1995
'Bryce mouse' (Bryce Canyon National Park)

Species: Bryceomys fumoses Eaton JG, 1995
Place: Straight Cliffs Formation, Utah
Country: USA
Age: Turonian, Upper Cretaceous
Remarks: Probably weighed about 12g, (half a house mouse). About a hundred teeth are held at the Oklahoma Museum of Natural History, including this holotype.
Reference: Eaton (1995), Cenomanian and Turonian (Early Late Cretaceous) multituberculate mammals from southwestern Utah., Journal of Vert Paleo 15(4), p.761-784.

Species: Bryceomys hadrosus Eaton JG, 1995
Place: Straight Cliffs Formation, Utah
Country: USA
Age: Turonian, Upper Cretaceous
Remarks: Also in the Oklahoma collection. Suggested bodyweight is around 90g.
Reference: Eaton (1995), Cenomanian and Turonian (Early Late Cretaceous) multituberculate mammals from southwestern Utah., Journal of Vert Paleo 15(4), p.761-784.

Species: Bryceomys intermedius Eaton JG & Cifelli RL, 2001
Place: Cedar Mountain Formation, Utah
Country: USA
Age: Albian (late) - Cenomanian (early), Upper Cretaceous
Reference: Eaton & Cifelli (2001), Multituberculate mammals from near the Early-Late Cretaceous boundary, Cedar Mountain Formation, Utah. Acta Palaeontologica Polonica 46(4), p.453-518

Page references: Kielan-Jaworowska Z & Hurum JH (2001), Phylogeny and Systematics of multituberculate mammals. Paleontology 44, p.389-429.

(This information has been derived from [1] (http://home.arcor.de/ktdykes/cimolod.htm) MESOZOIC MAMMALS; 'basal' Cimolodonta, Cimolomyidae, Boffidae and Kogaionidae, an internet directory. As that's my webpage, there are no issues of copyright. Trevor Dykes)