Paracimexomys

Paracimexomys is a genus of extinct mammals in the also extinct Multituberculata order. Paracimexomys lived during the Cretaceous period. The few fossils remains come from North America. Some Romanian fossils were also tentatively assigned to this genus, though that classification now seems doubtful.

The genus Paracimexomys ("beside Cimexomys") was named by Archibald J.D. in 1982. It is also known as Cimexomys sp. (Sloan & Van Valen, 1965). Paracimexomys fossils were originally referred as Cimexomys, until it was realized they were different enough to justify a genus of their own.

Species

• ?Paracimexomys crossi- Remains have been found in the Upper Aptian-Albian (Lower Cretaceous) strata of the Antlers Formation in Oklahoma, USA. Based on a tiny tooth, this was the first reported Oklahoma Mesozoic mammal. It's also the oldest known member of the informal Paracimexomys group. The species name honours the prison officer Bobby Cross, who has found this and other fossils.
• Paracimexomys magister also known as Cimexomys magister- Remains were found in the Upper Santonian (Upper Cretaceous) of Utah, USA. The animal probably weighed about 100g when it was alive.
• Paracimexomys magnus also known as Cimexomys magnus- Found in the Campanian (Upper Cretaceous) strata of the Judith River Formation in Montana, USA.
• Paracimexomys perplexus- Found in the late Albian to early Cenomanian (Upper Cretaceous) in the Cedar Mountain Formation of Utah.
• Paracimexomys priscus also known as Cimexomys priscus- Fossil remains were found in the Maastrichtian (Upper Cretaceous) of Hell Creek, Montana. Remains were first found in 1966. The holotype is in the collection of the University of Alberta, where the name Cimexomys is favoured. Weight is estimated to have been 60g.
• Paracimexomys robisoni Found in the Upper Cretaceous strata of the Cedar Mountain Formation of Utah. This type of fossil can be found in the Oklahoma Museum of Natural History. This mouse-sized animal weighed about 25g.
• ?Paracimexomys bestia seems to have possibly become Cedaromys bestia.

References

• Sahni, A (1972). "The vertebrate fauna of the Judith River Formation, Montana. Bulletin of the AMNH". Bulletin of the American Museum of Natural History 147. article 6. hdl:2246/1099. 
• Cifelli (1997). "First notice on Mesozoic mammals from Oklahoma". Oklahoma Geology Notes 57: 4–17. 
• Archibald (1982), "A study of Mammalia across the Cretaceous-Tertiary boundary in Garfield County, Montana". Univ. of Calif Publ Geol Sci 122 xvi, p. 1-286.
• Eaton, J; Nelson, M (1991). "Multituberculate mammals from the Lower Cretaceous Cedar Mountain Formation, San Rafael Swell, Utah". Contributions to Geology 29 (1): 1–12. 
• Eaton, J; Cifelli, R (2001). "Multituberculate mammals from near the Early-Late Cretaceous boundary, Cedar Mountain Formation, Utah" (PDF). Acta Palaeontologica Polonica 46 (4): 453–518. 
• Kielan-Jaworowska Z, Hurum JH (2001). "Phylogeny and Systematics of multituberculate mammals". Palaeontology 44 (3): 389–429. doi:10.1111/1475-4983.00185. 
• Much of this information has been derived from MESOZOIC MAMMALS; 'basal' Cimolodonta, Cimolomyidae, Boffidae and Kogaionidae, an Internet directory.