''Microbunodon'' was a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of extinct

artiodactyl The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing poster ...

mammals in the family

Anthracotheriidae Anthracotheriidae is a paraphyletic family of extinct, hippopotamus-like artiodactyl ungulates related to hippopotamuses and whales. The oldest genus, ''Elomeryx'', first appeared during the middle Eocene in Asia. They thrived in Africa and Eura ...

. It lived between the upper

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

and the lower

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

and

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

Description

''Microbunodon'', unlike most of its close relatives, was small in size and with a slight build. Its weight did not exceed 20–25 kilograms and the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

was about 20–30 centimeters long. ''Microbunodon'' was slim with long legs and a short snout with long prominent

canine teeth In mammalian oral anatomy, the canine teeth, also called cuspids, dog teeth, or (in the context of the upper jaw) fangs, eye teeth, vampire teeth, or vampire fangs, are the relatively long, pointed teeth. They can appear more flattened howeve ...

in males, similar to a

saber-toothed cat Machairodontinae is an extinct subfamily of carnivoran mammals of the family Felidae (true cats). They were found in Asia, Africa, North America, South America, and Europe from the Miocene to the Pleistocene, living from about 16 million ...

. It was characterized by a fused mandibular

symphysis A symphysis (, pl. symphyses) is a fibrocartilaginous fusion between two bones. It is a type of cartilaginous joint, specifically a secondary cartilaginous joint. # A symphysis is an amphiarthrosis, a slightly movable joint. # A growing togethe ...

, with a ventral ridge-like prominence.

Classification

The genus ''Microbunodon'' was established by Deperet in 1908 to accommodate a species previously described by Georges Cuvier in 1822 and attributed to the genus ''

Anthracotherium ''Anthracotherium'' (from el, ἄνθραξ , 'coal' and el, θηρίον 'beast') was a genus of extinct artiodactyl ungulate mammals, characterized by having 44 teeth, with five semi-crescentic cusps on the crowns of the upper molars. The ...

'', as ''A. minimum'', from the Oligocene superior of

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

, ''Microbunodon minimum'', lived in the Oligocene in Europe and is known in France,

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

, Switzerland,

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

and

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula in ...

. Other species attributed to this genus are ''M. silistrensis'' (early and middle Miocene,

Indian subcontinent The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...

and

Indochina Mainland Southeast Asia, also known as the Indochinese Peninsula or Indochina, is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to the west an ...

) and ''M. milaensis'' (late Miocene and early Pliocene, Indian subcontinent and Indochina). Other fossils attributed to this genus come from the upper Eocene of China and testify to an exceptional longevity of this evolutionary line (Tsubamoto, 2010). ''Microbunodon'' is an anthracothere, a group of artiodactyls usually considered similar to

hippopotami The hippopotamus ( ; : hippopotamuses or hippopotami; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extan ...

. ''Microbunodon'' represents an aberrant morphology for this family, whose members usually have large, heavy shapes. ''Microbunodon'' and '' Anthracokeryx'' have been placed in a separate subfamily, Microbunodontinae.Lihoreau F, Ducrocq S. 2007. Family Anthracotheriidae. In: Prothero DR, Foss SE, editors. The evolution of artiodactyls. Baltimore(MD): The Johns Hopkins University Press; p. 89–105.

Paleobiology

Analysis of dental wear of ''Microbunodon'' reveals that it probably had a diet based on leaves and fruit (Lihoreau, 2003). It likely lived in forest environments and had a lifestyle quite similar to that of musk deer and

mouse deer Chevrotains, or mouse-deer, are small even-toed ungulates that make up the family Tragulidae, the only extant members of the infraorder Tragulina. The 10 extant species are placed in three genera, but several species also are known only ...

. It is likely that it originated in Asia in the Eocene. At the end of the Oligocene, ''Microbunodon'' migrated to Europe and spread rapidly, along with other Artiodactyls. This event is known as the ''Microbunodon'' event, due to the significant impact that the invasion of these animals had on European fauna of the period (Scherler et al., 2013; Mennecart, 2015).

References

*Hünermann, K. A. von, 1967: Der Schädel von Microbunodon minus (Cuvier) (Artiodactyla, Anthracotheriidae) aus dem Chatt (Oligozän). Eclogue Geologicue Helvetica, vol. 60, p. 661–668. *Lihoreau, F., 2003. Systematique et paleoecologie des Anthracotheriidae (Artiodactyla; Suiformes) du Mio-Pliocene de l'Ancien Monde: Implications paleobiogeographiques. Unpublished These d'Universite, Universite de Poitiers *Lihoreau, F., Blondel, C., Barry, J. and Brunet, M., 2004: A new species of the genus Microbunodon (Anthracotheriidae, Artiodactyla) from the Miocene of Pakistan: genus revision, phylogenetic relationships and palaeobiogeography. Zoologica Scripta, vol. 33, p. 97–115. *T. Tsubamoto. 2010. Recognition of Microbunodon (Artiodactyla, Anthracotheriidae) from the Eocene of China. Paleontological Research 14(2):161-165 *Takehisa Tsubamoto, Thaung-Htike, Zin-Maung-Maung-Thein, Naoko Egi, Yuichiro Nishioka, Maung-Maung, and Masanaru Takai. (2012) New Data on the Neogene Anthracotheres (Mammalia, Artiodactyla) from Central Myanmar. Journal of Vertebrate Paleontology 32:4, 956-964. * Scherler L, Mennecart B, Hiard F, Becker D (2013) Evolution of terrestrial hoofed-mammals during the Oligocene-Miocene transition in Europe. Swiss Journal of Geosciences 106: 349–369. * Mennecart B (2015) The European Ruminants during the “Microbunodon Event” (MP28, Latest Oligocene): Impact of Climate Changes and Faunal Event on the Ruminant Evolution. PLoS ONE 10(2): e0116830. {{Taxonbar, from=Q20721950 Anthracotheres Oligocene even-toed ungulates Eocene even-toed ungulates Eocene genus first appearances Chattian genus extinctions Eocene mammals of Asia Oligocene mammals of Asia Oligocene mammals of Europe Prehistoric even-toed ungulate genera