Djadochtatherium is a mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

 genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 that lived in Mongolia

Mongolia

Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...

 during the Upper Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

. It coexisted with some of the late dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s. This animal was a member of the extinct order of Multituberculata

Multituberculata

The Multituberculata were a group of rodent-like mammals that existed for approximately one hundred and twenty million years—the longest fossil history of any mammal lineage—but were eventually outcompeted by rodents, becoming extinct during the early Oligocene. At least 200 species are...

. It's within the suborder of Cimolodonta

Cimolodonta

The Cimolodonta are a taxon of extinct mammals that lived from the Cretaceous to the Eocene. They were some of the more derived members of the extinct order Multituberculata. They probably lived something of a rodent-like existence until their ecological niche was assumed by true rodents...

, and a member of the family Djadochtatheriidae

Djadochtatheriidae

Djadochtatheriidae is a family of fossil mammals within the extinct order Multituberculata. Remains are known from the Upper Cretaceous of Central Asia. These animals lived during the Mesozoic, also known as the "age of the dinosaurs." This family is part of the suborder of Cimolodonta. The taxon...

. It was named by Simpson G.G. in 1925, the name meaning "Djadokhta beast."

The species Djadochtatherium matthewi was also named by Simpson G.G. in 1925 and has also been known as Catopsalis matthewi (Simpson GG, 1925). It has been found in the Campanian (Upper Cretaceous)-age Djadokhta and Goyot Formations of Mongolia. This was a relatively large Multituberculate, with a skull length of about 4.5 cm. It was originally diagnosed as a species within the North American genus of Catopsalis

Catopsalis

Catopsalis is a genus of extinct mammal from the Paleocene of North America, though some Canadian finds may be upper Cretaceous. This animal was a relatively large member of the extinct order of Multituberculata. Most Multituberculates were much smaller....

.