Anconodon
Encyclopedia
Anconodon is an extinct 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...

 of 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...

 from the 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...

 of 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 thus lived just after the "age of the dinosaurs
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

". It was a member of the extinct order 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...

 within the suborder 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 possibly the family Cimolodontidae
Cimolodontidae
Cimolodontidae is a family of fossil mammals within the extinct order Multituberculata. Representatives are known from the Upper Cretaceous and Paleocene of North America. There is some doubt as to whether Cimolodon is within this taxon. If not, the name of the family would still be valid...

.

The genus Anconodon was named by Jepsen G.L. in 1940. It is also known as Ectopodon (Russell 1967); Ectypodus (partly); Liotomus
Liotomus
Liotomus is a genus of extinct mammal from the Paleocene epoch . It lived in Europe and North America, and was a member of the extinct order Multituberculata, lying within the suborder Cimolodonta and possibly the family Cimolodontidae....

(partly); and Ptilodus
Ptilodus
Ptilodus is a genus of mammals from the extinct order of Multituberculata, and lived during the Paleocene in North America.Ptilodus was a relatively large multituberculate of in length, which is about the same size as a squirrel...

(partly).

Species

The species Anconodon cochranensis was named by Russell in 1929 and Van Valen and Sloan in 1966. It has also been known as A. russelli (Simpson 1935; Jepsen 1940); Ectopodon cochranensis (Russel 1967); Ectypodus cochranensis (Simpson 1937a); Ectypodus russelli (Simpson 1935d); Liotomus russelli; and Ptilodus cochranensis (Russell 1929). Fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 remains have been found in the Tiffanian (Middle-Upper Paleocene)-age 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...

 of Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...

 (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...

) and Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

 and Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 (USA). It has been cited as a descendant of A. gidleyi. The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 is in the University of Alberta
University of Alberta
The University of Alberta is a public research university located in Edmonton, Alberta, Canada. Founded in 1908 by Alexander Cameron Rutherford, the first premier of Alberta and Henry Marshall Tory, its first president, it is widely recognized as one of the best universities in Canada...

 collection. The body mass has been estimated to be about 55 g, the weight of two standard mice.

The species Anconodon gidleyi was named by Simpson G.G. in 1935 and Jepsen G.L. in 1940. It has also been known as A. gibleyi and Ptilodus ?gidleyi (Simpson 1935d). Fossil remains have been found in the Torrejonian (Middle-Upper Paleocene)-age strata of the Gidley Quarry in Montana and in Wyoming, New Mexico and Alberta. This species is cited as a possible descendant of Cimolodon
Cimolodon
Cimolodon is a genus of mammal from the Upper Cretaceous of North America. It was a member of the extinct order of Multituberculata within the suborder Cimolodonta and possibly the family Cimolodontidae....

 nitidus
.

The species: Anconodon lewisi was named by Sloan R.E. in 1987. Fossil remains were discovered in the Middle-Upper Paleocene-age strata of Keefer Hill in Wyoming and Douglass Quarry in Montana. The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

is from Wyoming.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK