Taeniolabidoidea is a group of extinct mammals known from North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

. They were the largest members of the also extinct order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 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...

. Lambdopsalis

Lambdopsalis

Lambdopsalis is a genus of mammal from the Paleocene of China. This animal was a relatively large member of the extinct order Multituberculata. It is placed within the suborder Cimolodonta and is a member of the superfamily Taeniolabidoidea....

even provides direct fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 evidence of mammalian fur

Fur

Fur is a synonym for hair, used more in reference to non-human animals, usually mammals; particularly those with extensives body hair coverage. The term is sometimes used to refer to the body hair of an animal as a complete coat, also known as the "pelage". Fur is also used to refer to animal...

 in a fairly good state of preservation for a 60-million-year-old animal. Some of these animals were large for their time; Taeniolabis

Taeniolabis

Taeniolabis is a genus of extinct mammal from the Paleocene of North America. It is the largest known member of the extinct order Multituberculata, reaching weights of perhaps 30 kg. It is within the suborder of Cimolodonta and is a member of the superfamily Taeniolabidoidea. The genus was named...

 taoensis is the largest known Multituberculate. Average members of the Taeniolaboidea were about beaver

Beaver

The beaver is a primarily nocturnal, large, semi-aquatic rodent. Castor includes two extant species, North American Beaver and Eurasian Beaver . Beavers are known for building dams, canals, and lodges . They are the second-largest rodent in the world...

-size and presumably beaver-heavy, up to about 30 kilograms.

The group was initially established as a suborder, before being assigned the rank of a superfamily by McKenna and Bell in 1997 (see Kielan-Jaworowska and Hurum (2001) p. 391-392). It's now strictly limited to the family Taeniolabididae. Some of the fossils are well-preserved. 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....

is known from 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...

 of Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, though the family is best represented in Paleocene

Paleocene

The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 strata

Stratum

In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...

.

Derived characteristics of the taxon

Taxon

|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

 (apomorphies) include: "snout short and wide with anterior part of zygomatic arch

Zygomatic arch

The zygomatic arch or cheek bone is formed by the zygomatic process of temporal bone and the temporal process of the zygomatic bone , the two being united by an oblique suture; the tendon of the Temporalis passes medial to the arch to gain insertion into the coronoid process...

es directed transversely, resulting in a square-like shape of the skull (shared with Kogaionidae

Kogaionidae

Kogaionidae is a family of fossil mammals within the extinct order Multituberculata. Representatives are known from the upper Cretaceous and the Paleocene of Europe. This family is part of the suborder Cimolodonta. Other than that, their systematic relationships are hard to define.These small...

); frontals small, pointed posteriorly, almost or completely excluded from the orbital rim," (Kielan-Jaworowska and Hurum 2001, p. 417).