Equidae is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. The family evolved around 50 million years ago from a small, multi-toed ungulate into larger, single-toed animals. All extant species are in the genus Equus, which originated in North America. Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and several extinct families. It is more specifically grouped within the superfamily Equoidea, the only other family being the extinct Palaeotheriidae.
Perissodactyla is an order of ungulates. The order includes about 17 living species divided into three families: Equidae, Rhinocerotidae (rhinoceroses), and Tapiridae (tapirs). They typically have reduced the weight-bearing toes to three or one of the five original toes, though tapirs retain four toes on their front feet. The nonweight-bearing toes are either present, absent, vestigial, or positioned posteriorly. By contrast, artiodactyls bear most of their weight equally on four or two of the five toes: their third and fourth toes. Another difference between the two is that perissodactyls digest plant cellulose in their intestines, rather than in one or more stomach chambers as artiodactyls, with the exception of Suina, do.
Tapirs are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a pig, with a short, prehensile nose trunk. Tapirs inhabit jungle and forest regions of South and Central America and Southeast Asia. They are one of three extant branches of Perissodactyla, alongside equines and rhinoceroses. Only a single genus, Tapirus, is currently extant. Tapirs migrated into South America during the Pleistocene epoch from North America after the formation of the Isthmus of Panama as part of the Great American Interchange. Tapirs were formerly present across North America, but became extinct in the region at the end of the Late Pleistocene, around 12,000 years ago.
The South American tapir, also commonly called the Brazilian tapir, the Amazonian tapir, the maned tapir, the lowland tapir, anta, and la sachavaca, is one of the four recognized species in the tapir family. It is the largest surviving native terrestrial mammal in the Amazon.
The mountain tapir, also known as the Andean tapir or woolly tapir, is the smallest of the four widely recognized species of tapir. It is found only in certain portions of the Andean Mountain Range in northwestern South America. As such, it is the only tapir species to live outside of tropical rainforests in the wild. It is most easily distinguished from other tapirs by its thick woolly coat and white lips.
Xenorhinotherium is an extinct genus of macraucheniine macraucheniids, native to northern South America during the Pleistocene epoch, closely related to Macrauchenia of Patagonia. The type species is X. bahiense.
The giant tapir is an extinct species of tapir that lived in southern China, Vietnam and Laos, with reports suggesting it also lived in Taiwan, Java, and potentially Borneo. The species has been recorded from Middle and Late Pleistocene. There is only weak evidence for a Holocene survival. Tapirus augustus was larger than any living tapir, with an estimated weight of about 623 kilograms (1,373 lb). The species was also placed in its own genus of Megatapirus, however, it is now conventionally placed within Tapirus.
Protapirus is an extinct genus of tapir known from the Oligocene and Miocene of North America and Eurasia.
Tapiroidea is a superfamily of perissodactyls which includes the modern tapirs and their extinct relatives. Taxonomically, they are placed in suborder Ceratomorpha along with the rhino superfamily, Rhinocerotoidea.The first members of Tapiroidea appeared during the Early Eocene, 55 million years ago, and were present in North America and Asia during the Eocene. Tapiridae first appeared during the early Oligocene in Europe, and are thought to have originated from the tapiroid family Helaletidae.
Tapirus californicus, the California tapir, is an extinct species of tapir that inhabited North America during the Pleistocene. It became extinct about 13,000 years ago.
Tapirus haysii is an extinct species of tapir that inhabited North America during the early to middle Pleistocene Epoch (~2.5–1 Ma). The fossil remains of two juvenile T. haysii were collected in Hillsborough County, Florida on August 31, 1963. It was the second largest North American tapir; the first being T. merriami.
Tapirus veroensis is an extinct tapir species that lived in the area of the modern eastern and southern United States during the Pleistocene epoch (Irvingtonian-Rancholabrean). Tapirus veronensis is thought to have gone extinct around 11,000 years ago.
Tapirus cristatellus is an extinct species of tapir from the Pleistocene of South America. Remains are known from Brazil, specifically the states of Minas Gerais and Bahia.
Tapirus greslebini is an extinct species of tapir that lived in South America during the Pleistocene.
Tapirus lundeliusi is an extinct species of tapir that lived in Florida in the early Pleistocene. It was similar in size and shape to the still-living mountain tapir, with an estimated weight of 203 kg
Tapirus mesopotamicus is an extinct species of tapir that lived in South America during the Pleistocene. It is considered a possible ancestor of all extant South American tapirs.
Tapirus oliverasi is likely an invalid extinct species of tapir from South America.
Tapirus rondoniensis is an extinct species of large sized tapir that lived in northwestern parts of Brazil during the Pleistocene. Fossils of the species were found in the Río Madeira Formation of Rondônia, after which the species is named.
Trichechus hesperamazonicus, the western Amazonian manatee, is an extinct species of manatee that lived about 40 thousand years ago in the Madeira River, in the Brazilian state of Rondonia. It is known from this single locality, with possible occurrences in the Brazilian state of Acre.
