''Simocyon'' ("short-snouted dog") is a genus of extinct

carnivora Carnivora is a Clade, monophyletic order of Placentalia, placental mammals consisting of the most recent common ancestor of all felidae, cat-like and canidae, dog-like animals, and all descendants of that ancestor. Members of this group are f ...

n mammal in the family

Ailuridae Ailuridae is a family in the mammal order Carnivora. The family consists of the red panda (the sole living representative) and its extinct relatives. Georges Cuvier first described ''Ailurus'' as belonging to the raccoon family in 1825; this cl ...

. ''Simocyon'', which was about the size of a

mountain lion The cougar (''Puma concolor'') is a large cat native to the Americas. Its range spans from the Canadian Yukon to the southern Andes in South America and is the most widespread of any large wild terrestrial mammal in the Western Hemisphere. ...

, lived in the late

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

and early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58

Classification

The relationship of ''Simocyon'' to other carnivores has been controversial, but studies of the structure of its ear, teeth, and ankle now indicate that its closest living relative is the

red panda The red panda (''Ailurus fulgens''), also known as the lesser panda, is a small mammal native to the eastern Himalayas and southwestern China. It has dense reddish-brown fur with a black belly and legs, white-lined ears, a mostly white muzzle ...

, '' Ailurus'' (Wang, 1997; Peigné et al., 2005), although it is different enough to be classified in a separate subfamily (Simocyoninae) along with related genera '' Alopecocyon'' and ''Actiocyon''. While the red panda is primarily herbivorous, the teeth and skull of ''Simocyon'' indicate that it was carnivorous, and it may have engaged in some bone-crushing, like living

hyena Hyenas, or hyaenas (from Ancient Greek , ), are feliform carnivoran mammals of the family Hyaenidae . With only four extant species (each in its own genus), it is the fifth-smallest family in the Carnivora and one of the smallest in the cl ...

s (Peigné et al., 2005). The skeleton of ''Simocyon'' indicates that, like the red panda, it could climb trees, although it probably also spent considerable time on the ground (Salesa et al., 2008). ''Simocyon'' and ''Ailurus'' both have a radial

sesamoid In anatomy, a sesamoid bone () is a bone embedded within a tendon or a muscle. Its name is derived from the Arabic word for 'sesame seed', indicating the small size of most sesamoids. Often, these bones form in response to strain, or can be prese ...

, an unusual bone in the wrist that acts as a false thumb (Salesa et al., 2006). Its competitors during its time period were tremarctine bears,

nimravid Nimravidae is an extinct family of carnivorans, sometimes known as false saber-toothed cats, whose fossils are found in North America and Eurasia. Not considered to belong to the true cats (family Felidae), the nimravids are generally considered ...

false cats, and early

canids Canidae (; from Latin, ''canis'', " dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within ...

and felids.

References

Bibliography

* Peigné, S., M. Salesa, M. Antón, and J. Morales. (2005). "Ailurid carnivoran mammal ''Simocyon'' from the late Miocene of Spain and the systematics of the genus." Acta Palaeontologica Polonica. Vol. 50:219-238. * Salesa, M. J., Antón, M., Peigné, S., and J. Morales. (2008). "Functional anatomy and biomechanics of the postcranial skeleton of ''Simocyon batalleri'' (Viret, 1929) (Carnivora, Ailuridae) from the late Miocene of Spain". Zoological Journal of the Linnean Society, vol. 152: 593–621. * Salesa, M., M. Antón, S. Peigné, and J. Morales. (2006). "Evidence of a false thumb in a fossil carnivore clarifies the evolution of pandas." Proceedings of the National Academy of Sciences. Vol. 103:379-382. * Wang, X. (1997). "New cranial material of ''Simocyon'' from China, and its implications for phylogenetic relationships to the red panda (''Ailurus'')." Journal of Vertebrate Paleontology. Vol. 17:184-198. Miocene carnivorans Pliocene carnivorans Neogene mammals of Africa Neogene mammals of Asia Neogene mammals of Europe Neogene mammals of North America Prehistoric carnivoran genera Ailuridae Miocene genus first appearances Zanclean extinctions Taxa named by Johann Andreas Wagner Fossil taxa described in 1858 {{paleo-carnivora-stub