Platygonus ("flat head" in reference to the straight shape of the forehead) is an extinct genus of herbivorous peccaries of the family Tayassuidae, endemic to North and South America from the Miocene through Pleistocene epochs (10.3 million to 11,000 years ago), existing for about . P. compressus stood tall.
Taxonomy While long thought to be the sister-lineage to the Chacoan peccary based on morphological similarities, a 2017 ancient DNA study which recovered mitochondrial DNA from Platygonus found that all living peccaries are more closely related to each other than they are to Platygonus. The estimated divergence between Platygonus and all living peccaries was placed in the Miocene, around 22 million years ago.
Platygonus was named by John Lawrence LeConte in 1848 for fossils found in Pleistocene karst deposits in Illinois, which are now preserved in the Academy of National Sciences in Philadelphia.
Species The following species of Platygonus have been described:
P. bicalcaratus (nomen dubium) P. brachirostris P. chapadmalensis P. cinctus P. compressus (type) P. kraglievichi P. marplatensis P. narinoensis P. oregonensis P. pearcei P. pollenae P. scagliae P. setiger P. striatus P. texanus P. vetus
Description
Most Platygonus species were similar in size to modern peccaries especially giant peccary, at around in body length, and had long legs, allowing them to run well. They also had a pig-like snout and long tusks that were probably used to fend off predators.
Ecology Like modern peccaries, Platygonus is thought to have lived in herds. Their remains are particularly abundant in caves, suggesting that they regularly used them. A study on the population structure of a population of P. compressus from Bat Cave, Missouri found that they had a similar demographic structure to modern peccaries, dominated by young adults, with a progressive attenuation of older adults due to predation and old-age, up to a maximum age of around 10 years. Platygonus is thought to have consumed tough foliage like leaves and grass. Platygonus preferred warm, temperate environments, and its presence at a site in areas like the Northeastern United States is used as an indicator of interglacial conditions.
Distribution During the Late Pleistocene, Platygonus was most common in Eastern North America, with records in the Great Plains and western North America being more sparse. In South America, Platygonus ranged from Colombia to Argentina.
Fossil localities Fossils of Platygonus have been found in:
Miocene Sheep Creek Formation, Nebraska
Chapadmalalan Chapadmalal Formation, Argentina
Hemphillian Beecher Island, Colorado Edson Beds, Kansas Rancho Viejo Beds, Mexico Devil's Nest Airstrip, Ogallala Group, Nebraska McKay and Rattlesnake Formations, Oregon Miami Quarry, Texas
Blancan Gila Conglomerate and St. David Formation, Arizona Palm Spring and San Diego Formations, California Tamiami Formation, Florida Glenns Ferry Formations, Idaho Ballard, Rexroad and Crooked Creek Formations, Kansas Rancho Viejo Beds, Mexico Tequixquiac, Mexico Panaca Formation, Nevada Camp Rice Formation, New Mexico Blanco and Love Formations, Texas Ringold Formation, Washington
Plio-Pleistocene Cocha Verde, Taminango, ColombiaCocha Verde at Fossilworks.org
Pleistocene Tarija Formation, Bolivia Palm Spring and Turlock Lake Formations, California Bermont and Wicomico Formations, Florida Yarbrough Cave, Georgia American Falls Lake Bed E Formation, Idaho Galena, Illinois (type locality)Galena at Fossilworks.org Harrodsburg Crevice, Indiana Turin Pit, Iowa Kingsdown and Crooked Creek Formations, Kansas Welch Cave, Kentucky Cumberland Bone Cave and Bushey Cavern, Maryland Tacubaya Formation, Mexico Geddes Lake barrow pit, Michigan Little Beaver Cave, Jacob's Cave, and Zoo Cave, Missouri Sappa Formation, Nebraska Dry Cave, New Mexico Sheriden Cave, Ohio Holloman Gravel Pit, Oklahoma Fossil Lake, Oregon Hanover Quarry and Platygonus vetus type locality, Pennsylvania Hot Springs Mammoth Site, South Dakota Laubach Cave, Seymour, Tule and Shuler Formations, Texas Early's Cave, Gardner's Cave, New Quarry Cave, Vickers Cave, Ruffners Cave, Virginia Hamilton Cave, Trout Cave, Poorfarm Cave, Patton Cave, West Virginia Hastings Highlands, OntarioLucas. The Cenozoic Biota of North Hastings. Independent. ISBN 9798296779526. Wellsch Valley, Saskatchewan Old Crow Flats, Yukon at ResearchGate.org
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