The species
Bryceomys fumosus (Eaton 1995) is known from
fossils found in
strata dating to the Turonian (Upper Cretaceous) in the Straight Cliffs Formation of
Utah, US. They probably weighed about 12g, about half the weight of a house mouse. About a hundred teeth are held at the
Oklahoma Museum of Natural History, including the
holotype. Species:
Bryceomys hadrosus Eaton J.G. 1995 Place:
Straight Cliffs Formation of Utah Age: Turonian (Upper Cretaceous) Also in the Oklahoma collection. Suggested bodyweight is around 90 g. Species:
Bryceomys intermedius Eaton JG & Cifelli RL, 2001 Place:
Cedar Mountain Formation, Utah Age: Albian (late) - Cenomanian (early) (Upper Cretaceous) ==References==