''Floridachoerus olseni'' is an extinct

peccary Peccaries (also javelinas or skunk pigs) are pig-like ungulates of the family Tayassuidae (New World pigs). They are found throughout Central and South America, Trinidad in the Caribbean, and in the southwestern area of North America. Peccari ...

that lived during the

Hemingfordian The Hemingfordian on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 20,600,000 to 16,300,000 years BP. It is usually considered to overlap the lates ...

age of the

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to ...

, and was endemic to

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

. ''F. olseni'' was in existence for approximately . Remains of this extinct mammal were located at the fossil rich Thomas Farm site in

Gilchrist County, Florida Gilchrist County is a County (United States), county located in the North Central Florida, north central part of the U.S. state of Florida. Organized in 1925 from the western part of Alachua County, Florida, Alachua, it is the last county to b ...

(two collections) and Toledo Bend site,

Newton County, Texas Newton County is the easternmost county in the U.S. state of Texas. As of the 2020 census, its population was 12,217. Its county seat is Newton. The county is named for John Newton, a veteran of the American Revolutionary War. Newton County ...

. ''Floridachoerus olseni'' was named after Stanley. J. Olsen of the Florida Geological Survey in 1962. Olsen previously worked at the site for

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

Lithology of sites

*Thomas Farm site: An ancient

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water ...

with an associated cave system not unusual for N. Florida. It's within a

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcare ...

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

and blue claystone. The fossils are from multiple horizons including a joint clay; a layer of clayballs, lime sand; a bed of

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

, boulders with gravel and lime sand matrix; and a laminated bluish clay. Most of the material is from the lime sand. The biochronology points to an early

origin through the presence of the ancient bear, ''

Phoberocyon ''Phoberocyon'' is a large extinct genus of Hemicyoninae, hemicyonine bear, found primarily in North America during the Miocene. It lived from 28.4 to 13.7 Annum, mya, existing for approximately . One species, ''P. hispanicus'', is known from Mi ...

'', the mustelid '' Leptarctus'', the rhino ''

Floridaceras ''Floridaceras'' is an extinct genus of rhinocerotid of the Miocene epoch (early Hemingfordian), endemic to North America, living from around ~20.6–16.3 Ma, existing for approximately . Taxonomy ''Floridaceras'' was named by Wood (1964). Its ...

'', and '' Metatomarctus'', a canid.Florida Museum of Natural History, Thomas Farm paleontological site
/ref> The Thomas Farm site is located on the

Alachua Formation The Alachua Formation is a Miocene Formation (stratigraphy), geologic formation in Florida. The claystones, sandstones and phosphorites of the formation preserve many fossils of mammals, birds, reptiles and fish, among others megalodon. Fossil c ...

. *Toledo Bend site: A coarse

palaeochannel In the Earth sciences, a palaeochannel, also spelled paleochannel, is a significant length of a river or stream channel which no longer conveys fluvial discharge as part of an active fluvial system. The term ''palaeochannel'' is derived from th ...

fill; a conglomerate likely from an episode of violent flood mixing of materials. (Albright, 1999). Also recovered with several mammals including two other Tayassuidae ('' Marshochoerus'', '' Hesperhys'') three species of rhino, two species of horse, the '' Dinohyus'', '' Daphoedon'', and '' Nothokemas''.

Lithology of sites

References

Further reading