The main species of Clemensodon is Clemensodon megaloba, however, this species is also known as a part of Kimbetohia campi. Fossils have been found in the Lance Formation of Wyoming (United States). They age from the Maastrichtian division of the Upper Cretaceous. The species is based on a reassessment of a couple of Kimbetohia teeth, but not the entire species or genus. The assignment of this taxon to Eucosmodontidae is tentative.
Evidence from the size and number of serrations of certain teeth and its enamel microstructure indicates that Clemensodon is either a derived taeniolabidoid or a primitive ptilodontoid. Determination of which of these two alternatives is correct must await the recovery of teeth from other positions.
Kielan-Jaworowska Z. and Hurum J.H. (2001), "Phylogeny and Systematics of multituberculate mammals". Paleontology44, p. 389-429.
Krause (1992), "Clemensodon megaloba, a new genus and species of Multituberculata (Mammalia) from the Upper Cretaceous Type Lance Formation, Powder River Basin, Wyoming". PaleoBios14(2), p. 1-8.