''Corriebaatar'' is an extinct genus of

multituberculate Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, a ...

mammals. It contains the single species ''Corriebaatar marywaltersae'' and represents the first evidence of

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

n multituberculates.Rich, T.H., Vickers-Rich, P., Flannery, T.F., Kear, B.P., Cantrill, D.J., Komarower, P., Kool, L., Pickering, D., Trusler, P., Morton, S., van Klaveren, N., and Fitzgerald, E.M.G. 2009. An Australian multitubercular and its palaeobiogeographic implications. Acta Palaeontologica Polonica 54(1):1-6

/ref> It is known from fossils found in the

Wonthaggi Formation The Wonthaggi Formation is an informal geological Formation (geology), formation in Victoria, Australia whose strata date back to the Early Cretaceous. It is part of the Strzelecki Group within the Gippsland Basin. Dinosaur remains are among the ...

date back to the

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

(latest

Barremian The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 125.77 Ma (million years ago) and 121.4 ± 1.0 Ma (Historically, this stage was placed at 129.4 million to approximately 125 million years ago) It is a ...

~ 125 million years ago).

Discovery

The species ''Corriebaatar marywaltersae'' was discovered in 2009 based on the discovery of a well-preserved fourth

premolar The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in ...

found in

Victoria, Australia Victoria, commonly abbreviated as Vic, is a state in southeastern Australia. It is the second-smallest state (after Tasmania), with a land area of ; the second-most-populated state (after New South Wales), with a population of over 7 million; ...

at the Flat Rocks fossil site. It was hypothesized to represent a

cimolodonta Cimolodonta is a clade of Multituberculata, multituberculate mammals that lived from the Cretaceous to the Eocene. They probably lived something of a rodent-like existence until their ecological niche was assumed by true rodents. The more basal ...

n multituberculate mammal as opposed to a new, unrecognized lineage. The 2009 specimen was the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

and the only known remains of the species until a second specimen of ''C. marywaltersae'' was discovered at the same site and described in 2022. The second specimen was two pieces of the lower jawbone that preserved both the fourth premolar and the first and second molars.

Taxonomy

It is placed as the only member of the family Corriebaataridae''. Corriebaatar'' was placed in the 2022 study as a derived multituberculate belonging to

Cimolodonta Cimolodonta is a clade of Multituberculata, multituberculate mammals that lived from the Cretaceous to the Eocene. They probably lived something of a rodent-like existence until their ecological niche was assumed by true rodents. The more basal ...

, and possibly closely related to ''

Ferugliotherium ''Ferugliotherium'' is a genus of fossil mammals in the family Ferugliotheriidae from the Campanian and/or Maastrichtian period (Late Cretaceous; around 70 million years ago) of Argentina. It contains a single species, ''Ferugliotherium windhaus ...

'' from the Late Cretaceous of Argentina.

References

Cimolodonta Fossil taxa described in 2009 Aptian life Cretaceous mammals of Australia Monotypic prehistoric mammal genera {{cretaceous-mammal-stub

Discovery

Taxonomy

See also

References