Chronoperates Temporal range: Late Paleocene,
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Symmetrodonta (?)
Family:	†Chronoperatidae Fox, Youzwyshyn & Krause, 1992
Genus:	†Chronoperates Fox, Youzwyshyn & Krause, 1992
Type species
†Chronoperates paradoxus Fox, Youzwyshyn & Krause, 1992

Chronoperates (meaning "time wanderer" in Greek) is an extinct genus of mammal whose remains have been found in a late Paleocene deposit in Alberta, Canada. It is represented by the type species Chronoperates paradoxus and known only from a partial left lower jaw.^[1] It was first identified in 1992 as a non-mammalian cynodont, implying a ghost lineage of over 100 million years since the previously youngest known record of non-mammalian cynodonts, which at that time was in the Jurassic period (some non-mammalian cynodonts are now known to have persisted until the Early Cretaceous). Subsequent authors have challenged this interpretation, particularly as the teeth do not resemble any known non-mammalian cynodonts. Chronoperates is now generally considered to be more likely to be a late-surviving symmetrodont mammal. This would still infer a ghost lineage for symmetrodonts, but a more plausible one, as symmetrodonts persisted into the Late Cretaceous.

References

http://darrennaish.blogspot.com/2006/05/time-wandering-cynodonts-and-docodonts.html https://web.archive.org/web/20081219051716/http://www.palaeos.com/Vertebrates/Units/410Cynodontia/410.400.html