Hippidion
Hippidion | |
---|---|
H. principale skeleton | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Perissodactyla |
Family: | Equidae |
Subfamily: | Equinae |
Tribe: | Equini |
Genus: | †Hippidion Owen, 1869 |
Species | |
| |
Synonyms | |
Hippidion (meaning little horse) is an extinct genus of equine that lived in South America from the Late Pliocene to the end of the Late Pleistocene (Lujanian), between 2.5 million and 11,000 years ago. They were one of two lineages of equines native to South America during the Pleistocene epoch, alongside Equus (Amerhippus) neogeus.
Taxonomy
Evolution
Although early ancient DNA analysis studies suggested a close relationship with the wild horse, Equus ferus,[1][2] this was later shown to be incorrect, with more complete sequences finding Hippidion as an outgroup to all living equines[3] and less closely related to living equines than the North American "New World stilt legged horse", Haringtonhippus francisci. Cladogram shown below:[4]
Equini | |
Hippidion is part of a distinct lineage of equines belonging to the tribe
Hippidion is traditionally thought to have 3 species, H. principale, H. saldiasi and H. devillei, however, in a 2015 DNA analysis, the single sampled H. principale specimen was found to be nested with H. saldiasi, while H. devillei was found to be clearly genetically distinct.[3]
Description
Specimens of Hippidion saldiasi have been estimated to weigh in the range of 252.7–326.4 kilograms (557–720 lb), while specimens of H. devillei have been estimated to weigh in the region of 227.3–366.5 kilograms (501–808 lb). H. principale was somewhat larger, with an estimated mass range of 252.7–468.6 kilograms (557–1,033 lb).[8] The skull of Hippidion is noted for its very long nasal notch separating the elongate nasal bone from the rest of the skull.[9] This structure is suggested to correspond to the presence of a prehensile upper lip.[10]
Paleobiology
Isotopic evidence from
Distribution
Fossils of Hippidion have been found across South America. Hippidion principale is primarily known from the Pampas grasslands of Argentina, but its range may have extended to Peru and Ecuador. Hippidion devillei is also known from Argentinan Pampas, but is also found in the Peruvian central Andes, with remains possibly found in Venezuela. Hippidion saldiasi was native to the Southern Cone, including Patagonia and the southern Andes.[8]
Extinction
Hippidion became extinct alongside the other South American equines at the end of the Late Pleistocene, between 12,000 and 10,000 years
References
- ^ PMID 15974804.
- ^ S2CID 19069554.
- ^ PMID 25762573.
- ^ PMID 29182148.
- ^ ISSN 0272-4634.
- ^ a b MacFadden, B. J., and M. Skinner. 1979. Diversification and biogeography of the one-toed horses Onohippidium and Hippidion. Yale Peabody Museum of Natural History Postilla 175:1–9.
- .
- ^ S2CID 233706381.
- ISBN 978-3-319-55876-9, retrieved 2024-01-19
- .
- PMID 21672241.
- ISBN 978-3-319-55876-9, retrieved 2024-01-20
- S2CID 210240458.
- ISSN 2296-701X.
- S2CID 253876769.