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H.-D. Sues contests the identification of Chronoperates as a Paleocene therapsid reptile, and implies that it must be a mammal instead. But Sues does not specify which of the several competing definitions of mammals he has in mind, so it is not clear by what criteria he classifies Chronoperates as a mammal. Also, he dismisses the therapsid-like dental features as artefacts of preservation, not legitimate anatomical features. But since he has never examined the specimen, this reflects only his expectation. The evidence supports identification of Chronoperates as a therapsid.

The anatomical evidence relating to the fossil Chronoperates paradoxus discounts the claim that this specimen is a 'mammal-like reptile' or nonmammalian synapsids whose discovery in the Paleocene of Alberta, CN, shows that such animals were alive 100,000 years later than is commonly thought. A new anatomical examination of the fossil's postcanines, pseudoprismatic enamel, alleged postdentary bones and masseteric fossa casts doubt on the classification of this species as a nonmammalian cynodont.

The discovery of fossils from a therapsid or mammal-like reptile in the upper Paleocene Paskapoo Formation in Alberta, Canada, extends the known existence of these animals to 100 million years later than was previously thought. Therapsids are believed to be the evolutionary link between reptiles and mammals. Fox and colleagues, who found the fossils, call the new animal Chronoperates paradoxus and classify it as a therapsid based on several anatomical features such as the tooth enamel's microstructure. However, this classification will remain tentative until further evidence proves it.