genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of bear endemic to
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
from the
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
to the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Mya, existing for about 7 million years.
''
Indarctos
''Indarctos'' is an extinct genus of bear, endemic to North America, Europe and Asia during the Miocene. It was present from ~11.1 to 5.3 Ma, existing for approximately .
The oldest member is from Arizona (~11.1—7.7 Ma) and youngest is (~9.0 ...
'' (10.7—9.2 Mya) preceded ''Plionarctos'' by only a few thousand years and was a contemporary of that bear and shared its habitat. ''Plionarctos'' preceded and was also contemporary with ''
Tremarctos floridanus
''Tremarctos floridanus'', occasionally called the Florida spectacled bear, Florida cave bear, or rarely Florida short-faced bear, is an extinct species of bear in the family Ursidae, subfamily Tremarctinae. ''T. floridanus'' was widespread in ...
'' (4.9 million — 11,000 years ago) and shared its habitat. ''Plionarctos'' is the oldest known genus within the subfamily of the short-faced bears (
Tremarctinae
The Tremarctinae or short-faced bears is a subfamily of Ursidae that contains one living representative, the spectacled bear (''Tremarctos ornatus'') of South America, and several extinct species from four genera: the Tremarctos floridanus, Florid ...
), and is believed to be ancestral to the
clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
.
Fossil distribution
Sites and specimen ages:
*Ile de Ratonneau Breccia,
Provence, France
Provence (, , , , ; oc, Provença or ''Prouvènço'' , ) is a geographical region and historical province of southeastern France, which extends from the left bank of the lower Rhône to the west to the Italian border to the east; it is bor ...
about ~800,000—100,000 years ago
*Fort Green Mine,
Polk County, Florida paleontological sites
The Polk County paleontological sites are assemblages of Early Miocene to Late Pleistocene vertebrates occurring in Polk County, Florida, United States.
Age
Era: Neogene
Period: Miocene to Pleistocene, ~17.7—1.5 Mya. (calculates to a perio ...
about 10.3—4.9 Mya
*Taunton site,
Adams County, Washington
Adams County is a county in the U.S. state of Washington. As of the 2020 census, the population was 20,613. The county seat is at Ritzville, and its largest city is Othello. The county was formed out of Whitman County in November 1883 and is ...
''(P. harroldorum)'' about 4.9—1.8 Mya (''Plionarctos harroldorum'')
*
Pipe Creek Sinkhole The Pipe Creek Sinkhole near Swayzee in Grant County, Indiana, is one of the most important paleontological sites in the interior of the eastern half of North America. It is preserved because it was buried by glacial till. Uncovered in 1996 by wo ...
,
Grant County, Indiana
Grant County is a County (United States), county in central Indiana in the United States Midwest. At the time of the 2020 census, the population was 66,674. The county seat is Marion, Indiana, Marion. Important paleontology, paleontological disc ...
''(P. edensis)'' about 10.3—1.8 Mya
*Palmetto Mine,
Polk County, Florida
Polk County is located in the central portion of the U.S. state of Florida. The county population was 725,046, as of the 2020 census. Its county seat is Bartow, and its largest city is Lakeland.
Polk County comprises the Lakeland–Winter Ha ...
7.9—7.8 Mya
*
Gray Fossil Site
The Gray Fossil Site is an Early Pliocene assemblage of fossils dating between 4.5 and 4.9 million years old, located near the town of Gray in Washington County, Tennessee. The site was discovered during a widening project of Tennessee State Route ...
,
Washington County, Tennessee
Washington County is a county located in the U.S. state of Tennessee. As of the 2020 census, the population was 133,001. Its county seat is Jonesborough. The county's largest city and a regional educational, medical and commercial center is ...