''Mirocetus'' is a genus of archaic odontocete from the late Oligocene (

Chattian The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest stage ...

) of Azerbaijan. Like many other primitive odontocetes, its classification has been fluid since its description.

Classification

''Mirocetus riabinini'' is based on a skull from late Oligocene (Chattian) deposits in Azerbaijan. Although originally assigned to Patriocetidae in the original description, it was later assigned to the mysticete family

Aetiocetidae Aetiocetidae is an extinct family of toothed baleen whales known from the Oligocene. The whales are from the North Pacific Ocean and ranged in size from long. Many of the described specimens were discovered from the Upper Oligocene of the Japa ...

by Mchedlidze (1976). Fordyce (1981, 2002) treated ''Mirocetus'' as Odontoceti incertae sedis in recognition of its primitiveness, and a 2015 paper by Albert Sanders and Jonathan Geisler recognized the genus as sufficiently distinct from other basal odontocete families to warrant its own family, Mirocetidae. However, a cladistic analysis of '' Olympicetus'' by Velez-Juarbe (2017) recovers ''Mirocetus'' as a member of

Xenorophidae Xenorophidae is an extinct family of odontocetes currently known from the Oligocene of the southeastern US. Known genera of xenorophids include '' Albertocetus'', '' Archaeodelphis'', ''Xenorophus ''Xenorophus'' is a genus of primitive odonto ...

, rendering Mirocetidae a synonym of Xenorophidae.

References

{{Taxonbar, from=Q37754721 Xenorophidae Fossil taxa described in 1970 Prehistoric cetaceans Oligocene cetaceans