The species
Stygimys camptorhiza was named by P.A. Johnston and R.C. Fox in
1984. Place:
Puercan (Paleocene)-age
strata of Rav W-1 in
Saskatchewan, Canada. The
holotype for this species is in the
University of Alberta collection. The species
Stygimys cupressus was named by R.C. Fox in
1989. Remains are known from the Puercan (Paleocene)-age strata of the Long Fall Horizon of Canada. The species
Stygimys jepseni was named by
George Gaylord Simpson in
1935 and Sloan and Van Valen in 1965. It is also known as
Eucosmodon sparsus (Simpson 1937a);
E. jepseni; and
Parectypodus jepseni (Simpson 1935d). Remains are known from the Torrejonian (Paleocene)-age strata of
Montana (USA). This species has been cited as a descendant of
S. kuszmauli. The animal weighed about 90 g. The species
Stygimys kuszmauli was named by R.E. Sloan and Leigh Van Valen in 1965. It has also been known as
Catopsalis foliates (Cope 1882);
Cimexomys gratus (Jepsen GL,
1930);
Eucosmodon gratus (G.L. Jepson 1930);
Eucosmodon kuszmauli ; and
Stygimys gratus. Remains were found in
Maastrichtian (Upper Cretaceous) - Puercan (Paleocene)-age strata of the
Polecat Bench Formation of
Wyoming and the
Hell Creek Formation of Montana. Some scraps of jaw are known. This species is the most basal member of the genus, with a weight of 300 g. The species
Stygimys teilhardi was named by W. Granger & George Gaylord Simpson in
1929 and R.E. Sloan and Leigh Van Valen in 1965. It has also been known as
Eucosmodon teilhardi (Granger W. & Simpson G.G. 1929). Remains are known from the
Torrejonian (Paleocene)-age strata of the
San Juan Basin of
New Mexico. This species has been cited as a possible descendant of
S. kuszmauli. == References ==