| Protapirus | |
|---|---|
 | |
| Mandible of Protapirus priscus | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Perissodactyla |
| Family: | Tapiridae |
| Genus: | † Protapirus Filhol, 1877 |
| Type species | |
| †Protapirus priscus Filhol, 1874 | |
| Species | |
| |
Protapirus (Latin: "before" (pro), + Brazilian Indian: "tapir" (tapira) [1] ) is an extinct genus of tapir known from the Oligocene and Miocene of North America and Eurasia. [2]
The type species is Protapirus priscus from the Late Oligocene of Quercy, France. [3] Protapirus is often considered the earliest true tapir, or at least a tapiroid that is the direct ancestor of the true tapir family. [4]
The oldest species is the North American P. simplex from the White River Formation. A later North American species is P. obliquidens From North America, the genus spread into Eurasia during the Oligocene, [5] with five species known from the Oligocene and Miocene of Europe and a single species (P. gromovae) from Kazakhstan. [6]
They were of similar size to modern tapirs, but had more primitive features, such as premolars that were less molariform in shape. In comparison to more primitive tapiroids, Protapirus had retracted nasal region which may indicate the presence of a trunk. [7] However, the nasals were not as shortened as in modern tapirs, so the proboscis would have likely been less prominent. [8]
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 odd-toed ungulates digest plant cellulose in their intestines, rather than in one or more stomach chambers as even-toed ungulates, 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.
Tapirus is a genus of tapir which contains the living tapir species. The Malayan tapir is usually included in Tapirus as well, although some authorities have moved it into its own genus, Acrocodia.
Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch. The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed.
Hyaenodon ("hyena-tooth") is an extinct genus of carnivorous placental mammals from extinct tribe Hyaenodontini within extinct subfamily Hyaenodontinae, that lived in Eurasia and North America from the middle Eocene, throughout the Oligocene, to the early Miocene.
Chalicotheriidae is an extinct family of herbivorous, odd-toed ungulate (perissodactyl) mammals that lived in North America, Eurasia, and Africa from the Middle Eocene until the Early Pleistocene, existing from 48.6 to 1.806 mya. They are often called chalicotheres, a term which is also applied to the broader grouping of Chalicotherioidea. They are noted for their unusual morphology compared to other ungulates, such as their elongated clawed forelimbs. They are thought to have been browsers.
Ancylotherium is an extinct genus of the family Chalicotheriidae, subfamily Schizotheriinae, endemic to Europe, Asia, and Africa during the Late Miocene-Early Pleistocene, existing for approximately 9.8 million years.
Metamynodon is an extinct genus of amynodont that lived in North America and Asia from the late Eocene until early Oligocene, although the questionable inclusion of M. mckinneyi could extend their range to the Middle Eocene. The various species were large, displaying a suit of semiaquatic adaptations more similar to those of the modern hippopotamus, despite their closer affinities with rhinoceroses.
Eomyidae is a family of extinct rodents from North America and Eurasia related to modern day pocket gophers and kangaroo rats. They are known from the Middle Eocene to the Late Miocene in North America and from the Late Eocene to the Pleistocene in Eurasia. Eomyids were generally small, but occasionally large, and tended to be squirrel-like in form and habits. The family includes the earliest known gliding rodent, Eomys quercyi.
Amynodontidae is a family of extinct perissodactyls related to true rhinoceroses. They are commonly portrayed as semiaquatic hippo-like rhinos but this description only fits members of the Metamynodontini; other groups of amynodonts like the cadurcodontines had more typical ungulate proportions and convergently evolved a tapir-like proboscis.
Parictis is an extinct arctoid belonging to the family Subparictidae.
Chilotherium is an extinct genus of rhinocerotids endemic to Eurasia during the Miocene through Pliocene living for 13.7—3.4 mya, existing for approximately 10.3 million years.
Archaeohippus is an extinct three toed member of the family Equidae known from fossils of early Oligocene to middle Miocene age. The genus is noted for several distinct skeletal features. The skull possesses deeply pocketed fossa in a notably long preorbital region. The genus is considered an example of phyletic dwarfism with adults estimated at being on average 20kg in weight. This is in contrast to the most common equid of the period, Miohippus. Characters of the teeth show a mix of both primitive and advanced traits. The advanced traits are very similar to those shown in the genus Parahippus. The noted similarities of Archaeohippus and Parahippus show them to be descended from a common ancestor and are considered sister species.
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.
Pterodon is an extinct genus of hyaenodont in the family Hyainailouridae, containing five species. The type species Pterodon dasyuroides is known exclusively from the late Eocene to the earliest Oligocene of western Europe. The genus was first erected by the French zoologist Henri Marie Ducrotay de Blainville in 1839, who said that Georges Cuvier presented one of its fossils to a conference in 1828 but died before he could make a formal description of it. It was the second hyaenodont genus with taxonomic validity after Hyaenodon, but this resulted in taxonomic confusion over the validities of the two genera by other taxonomists. Although the taxonomic status of Pterodon was revised during the late 19th and early 20th centuries, it became a wastebasket taxon for other hyaenodont species found in Africa and Asia. Today, only the type species is recognized as belonging to the genus while four others are pending reassessment to other genera.
Homogalax is an extinct genus of tapir-like odd-toed ungulate. It was described on the basis of several fossil finds from the northwest of the United States, whereby the majority of the remains come from the state of Wyoming. The finds date to the Lower Eocene between 56 and 48 million years ago. In general, Homogalax was very small, only reaching the weight of today's peccaries, with a maximum of 15 kg. Phylogenetic analysis suggests the genus to be a basal member of the clade that includes today's rhinoceros and tapirs. In contrast to these, Homogalax was adapted to fast locomotion.
Palaeotapirus is an invalid genus of tapir.
This paleomammalogy list records new fossil mammal taxa that were described during the year 2013, as well as notes other significant paleomammalogy discoveries and events which occurred during that year.
Nexuotapirus is an extinct genus of tapir from the Late Oligocene and Early Miocene of North America.
Paratapirus is an extinct genus of tapir known from the Late Oligocene and Early Miocene of Europe.
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