Parectypodus is a genus of extinct mammal that lived from the Paleocene to the Eocene of North America. Some of the known fossil material may also be from the Upper Cretaceous. It was a member of the extinct order of Multituberculata, and it lies within the suborder of Cimolodonta, family Neoplagiaulacidae. The genus was named by Jepsen G.L. in 1930 and means ‘beside Ectypodus'. The genus has also been known as Ectypodus (partly); Mimetodon (partly); Neoplagiaulax (partly); "Parectypodus"; Perectypodus; Ptilodus (partly)
. P. jepseni is a junior synonym for Stygimys jepseni.

Species: Parectypodus armstrongi Johnston PA & Fox RC, 1984
Place: Rav W-1, Saskatchewan, Canada
Age: Puercan, Paleocene
Resides in the collection of Alberta University.

Species: Parectypodus foxi Storer JE, 1991
Age: Maastrichtian, Upper Cretaceous br> Estimated to have weighed about 80g.

Species: Parectypodus laytoni (JepsenGL, 1940) Sloan RE, 1966
Aka: Ectypodus laytoni Jepsen, 1940
Place: Princeton Quarry, Wyoming
Age: lower Tiffanian, Middle-Upper Paleocene
Has been cited as a descendant of P. sinclairi. A mini-representative, having a weight of perhaps 10g.

Species: Parectypodus lunatus Krause DW, 1982
Aka: P. childei (Kühne, 1969)
Place: Pocket Quarry, Colorado and Wyoming
Age: Wasatchian, Lower Eocene
This is a late species, having a weight of about 35g.

Species: Parectypodus sinclairi (Lamb, 1902) Clemens, 1964a
Aka: Ectypodus sinclairi Simpson, 1935; Ptilodus sinclairi Simpson, 1935d
Place: Gidley Quarry, Montana, Wyoming amd Alberta, Canada.
Age: Puercan-Torrejonian, Paleocene
This species has been cited as having derived from Mesodma formosa. A smaller species of about 15g, which might also go under the name of Liotomus sinclairi.

Species: Parectypodus sloani Schiebout JA, 1974
Aka: Ectypodus sloani
Fossils of this species has been found in the Torrejonian (Paleocene)-age beds of Big Bend, Texas

Species: Parectypodus sylviae (Rigby JK, 1980) Sloan, 1987
Aka: Ectypodus sylviae Rigby JK, 1980; ?Ectypodus aphronorus Sloan RE, 1987; P. Pattersoni Sloan, 1987 Place: Swain Quarry, Montana and Wyoming
Age: Torrejonian, Paleocene
Body weight estimate, 15g. In 1998, Secord synonymized pattersoni with sylviae.

Species: Parectypodus trovessartianus (Cope ED, 1882) Van Valen & Sloan, 1966
Aka: Mimetodon trouessartianus Jepsen, 1940; Neoplagiaulax trouessarti; "P. trouessarti"; Ptilodus trouessarti; Ptilodus trouessartianus Cope, 1882
Place: San Juan Basin, New Mexico
Age: Puercan-Torrejonian, Paleocene
Body mass of around 90g.

References

• Jepsen (1930), New vertebrate fossils from the lower Eocene of the Bighorn Basin, Wyoming. Proc. Am. Phil. Soc. LXIX, p.117-131.
• Jepsen (1940), Paleocene faunas of the Polecat Bench formation, Park County, Wyoming. Pro. Amer. Philos. Soc, 83, p.217-340, 21 figs., 5pls.
• Simpson (1935), New Paleocene mammals from the Fort Union of Montana. Proc. US Nation. Museum 83, p.221-244.
• Schiebout (1974), Vertebrate paleontology and paleoecology of Paleocene Black Peaks Formation, Big Bend National Park, Texas. Texas Memorial Museum Bull. 24: 1-87.
• Johnston and Fox (1984), Paleocene and Late Cretaceous mammals from Saskatchewan, Canada. Paleontogr. Abt. A: Paläozool., Stratigr. 186, p.163-222.
• Kielan-Jaworowska Z. and Hurum J.H. (2001), Phylogeny and Systematics of multituberculate mammals. Paleontology 44, p.389-429.
• Much of this information has been derived from [1] (http://home.arcor.de/ktdykes/ptilodon.htm) MESOZOIC MAMMALS; Ptilodontoidea, an Internet directory.