''Ptilodus'' (meaning "soft-haired") is a genus of mammals from the extinct order of

Multituberculata 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 ...

, and lived during the

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...

in North America. ''Ptilodus'' was a relatively large multituberculate of in length, which is about the same size as a squirrel. Its feet, legs and long tail suggest it was a good climber, so it very possibly led a squirrel-like lifestyle. The genus was named by

paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

Edward Drinker Cope in 1881. Cope also mistakenly assigned some material belonging to this genus to ''Chirox'' in 1884. Elements from '' Ectypodus'' (Jepsen, 1940) and ''

Neoplagiaulax ''Neoplagiaulax'' is a mammal genus from the Paleocene of Europe and North America. In the case of the latter continent, there may possibly be some slightly earlier, Upper Cretaceous material too. It existed in the age immediately following the e ...

'' have also been reassigned to this genus.

Species

There are seven

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, and others have been proposed at one time or another. ''P. nellieae'' (Bell, 1941) is apparently mentioned in a manuscript, rather than a publication. ''P. sinclairi'' (

Simpson Simpson most often refers to: * Simpson (name), a British surname *''The Simpsons'', an animated American sitcom **The Simpson family, central characters of the series ''The Simpsons'' Simpson may also refer to: Organizations Schools *Simpso ...

, 1935) seems to have become '' Parectypodus sinclairi''. In

botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

, ''Ptilodus pyramidatus'' is an extinct Australian plant.

''P. fractus''

The species ''Ptilodus fractus'' had a body weight of about . Remains have been found in

Wyoming Wyoming () is a state in the Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to the s ...

, in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

, in Dell Creek deposits dated to the Tiffanian

stage Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * Sta ...

of the Paleocene. The species was named by J. A. Door in 1952 ( Scott ''et al.'', 2002, Dorr, 1952), though it may have been amended to its current state by David Krause in 1987.

''P. gnomus''

''Ptilodus gnomus'' is the smallest known member of the genus. Hence, the species epithet 'gnomus', which is

New Latin New Latin (also called Neo-Latin or Modern Latin) is the revival of Literary Latin used in original, scholarly, and scientific works since about 1500. Modern scholarly and technical nomenclature, such as in zoological and botanical taxonomy ...

for 'dwarf'. Remains have been discovered in Wyoming in the United States, and

Alberta Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...

, Canada. They were recovered from the Cochrane 2 deposits of the Paskapoo Formation, which have been dated to the Tiffanian stage of the Paleocene. Remains of this species include over 100

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

, (upper and lower), and at least one fragment of jaw. The teeth range from in length. The fourth lower premolar (p4) is about 51% shorter than the corresponding tooth in ''P. mediaevus''; 28% less than ''P. kummae''; 15% less than ''P. tsosiensis''; and 5% smaller than ''P. fractus'', which gives some idea of the relative sizes of the various animals. There are also differences in shape and the number of serrations. ( Scott ''et al.'', 2002) :Although more similar in size to homologous teeth referable to ''P. tsosiensis'' and ''P. fractus'', the upper and lower ultimate premolars of this new species most closely resemble those of ''P. mediaevus'' in overall morphology. ( Scott ''et al.'', 2002) A couple of isolated teeth which had been previously identified as perhaps belonging to ''Ectypodus'', have been now been placed within this taxon. All referred specimens are held in the collection of the

University of Alberta The University of Alberta, also known as U of A or UAlberta, is a Public university, public research university located in Edmonton, Alberta, Canada. It was founded in 1908 by Alexander Cameron Rutherford,"A Gentleman of Strathcona – Alexande ...

. The species was named by C. R. Scott, R. C. Fox, and G. P. Youzwyshyn in 2002. Material assigned by Jepsen in 1940, as amended by Gazin in 1956, to ''Ectypodus hazeni'' has also been assigned to this species. There are three species of this

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

known from the Alberta location, two of which have yet to be described. This will be attended to by David W. Krause. ( Scott ''et al.'', 2002, pg. 691).

''P. kummae''

''Ptilodus kummae'' has an estimated weight of . Remains have been discovered in Roche Percée,

Saskatchewan Saskatchewan ( ; ) is a province in western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on the south by the U.S. states of Montana and North Dak ...

in Canada, in deposits from the lower Tiffanian stage of the Paleocene. The species was named by David W. Krause in 1977. ( Krause, 1977) The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

is at Alberta University.

''P. mediaevus''

Remains of ''Ptilodus mediaevus'' have been recovered in

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ke ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

, and Wyoming in the United States. They have been unearthed from the deposits of the San Juan Basin, which are dated to the Torrejonian stage of the Paleocene. Cope named the species in 1881 ( Cope, 1881). The species ''Ptilodus feronensis'', or ''Ptilodus ferronensis'', was named C. L. Gazin in 1941 ( Gazin, 1941), but all material was reassigned to ''P. mediaevus'' by Rigby in 1980. In 1929, Granger and Simpson did the same thing to the species ''P. plicatus'', which was originally named by

J. W. Gidley James Williams Gidley (1866-1931) was an American paleontologist and museum curator.James W. Gi ...

in 1909. ''Chirox plicatus'' was named by Cope in 1884. He described it as a

marsupial Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a ...

in 1884, but it is also part of this species.

''P. montanus''

''Ptilodus montanus'' is a large species, about . A brain cast indicates a well-developed sense of smell. Remains were recovered in Montana, in the rock of the Silberling Quarry, which is dated to the lower Tiffanian stage of the Paleocene. The species was named by E. Douglass in 1908 ( Douglass, 1908). The species ''P. admiralis'', first described by Hay in 1930; and ''P. gracillis'', first described by

J. W. Gidley James Williams Gidley (1866-1931) was an American paleontologist and museum curator.James W. Gi ...

in 1909 ( Gidley, 1909) are now considered part of this species.

''P. tsosiensis''

''Ptilodus tsosiensis'' has been discovered in New Mexico, the Puercan stage deposits of the Lower Paleocene San Juan Basin. The species was named by R. E. Sloan in 1981 ( Sloan, 1981).

''P. wyomingensis''

Remains of ''Ptilodus wyomingensis'' have been found in the Middle Paleocene deposits of the Rock Bench Quarry, in Wyoming and

North Dakota North Dakota () is a U.S. state in the Upper Midwest, named after the indigenous Dakota Sioux. North Dakota is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, So ...

in the United States. The species was named by G. L. Jepsen in 1940 ( Jepsen, 1940).

References

* G. L. Jepsen (1940). Paleocene faunas of the Polecat Bench formation, Park County. ''Wyoming. Pro. Amer. Philos. Soc'' 83, 217–340. * Z. Kielan-Jaworowska & J. H. Hurum (2001). Phylogeny and Systematics of multituberculate mammals. ''Paleontology'' 44, 389–429. * David Krause (1977). Paleocene multituberculates (Mammalia) of the Roche Percee Local Fauna, Ravenscrag Formation, Saskatchewan, Canada. ''Palaeontographica Abt'', A 186, 1–36. * C. R. Scott, R. C. Fox RC, and G. P. Youzwyshyn (2002). New earliest Tiffanian (late Paleocene) mammals from Cochrane 2, southwestern Alberta, Canada. ''Acta Palaeontologica Polonica'' 47 (4), 691–704. * R. E. Sloan (1981). Systematics of Paleocene multituberculates from the San Juan Basin, New Mexico. In Lucas ''et al.'' (Ed.), ''Advances in San Juan Basin paleontology'', 127–160. University of New Mexico Press, Albuquerque. * * Much of this information has been derived fro
MESOZOIC MAMMALS; Ptilodontoidea
an Internet directory. {{Taxonbar, from=Q783958 Paleocene mammals of North America Ptilodontoids Paleocene mammals Taxa named by Edward Drinker Cope Fossil taxa described in 1881 Prehistoric mammal genera