Eurhinodelphis Temporal range: | |
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Skeleton of E. longirostris | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Artiodactyla |
Infraorder: | Cetacea |
Family: | † Eurhinodelphinidae |
Genus: | † Eurhinodelphis Du Bus, 1867 |
Species | |
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Eurhinodelphis ("well-nosed dolphin") is an extinct genus of Miocene cetacean. Its fossils have been found in Belgium, France, and Maryland.
Currently-valid species are: [1]
Former species include:
Eurhinodelphis was around 2 metres (6.6 ft) in length. In most respects, it would have looked like a modern dolphin or porpoise, but its upper jaw was elongated into a sharp tip similar to that of a swordfish. Most likely, Eurhinodelphis used it in a similar manner to swordfish, hitting or stabbing prey. It also had long, sharp teeth. [2]
Compared with earlier fossil species, Eurhinodelphis had complex ears, suggesting that it already hunted by echolocation like modern whales. Its brain was also asymmetrical, a trait found in modern dolphins, and possibly associated with the complexities of navigating its environment. [2]
Eurhinodelphis was first described by B. Du Bus in a paper read before the Royal Academy of Sciences of Belgium on 17 December 1867. O. Abel studied and illustrated the European species in a series of articles published in 1901, 1902 and 1905; subsequently, fossil skulls found in the Calvert Formation in Maryland and Virginia could be attributed to this genus.
Moeritherium is an extinct genus of primitive proboscideans. These prehistoric mammals are related to the elephant and, more distantly, sea cows and hyraxes. They lived during the Eocene epoch.
Sivapithecus is a genus of extinct apes. Fossil remains of animals now assigned to this genus, dated from 12.2 million years old in the Miocene, have been found since the 19th century in the Siwalik Hills of the Indian subcontinent as well as in Kutch. Any one of the species in this genus may have been the ancestor to the modern orangutans.
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Platecarpus is an extinct genus of aquatic lizards belonging to the mosasaur family, living around 84–81 million years ago during the middle Santonian to early Campanian, of the Late Cretaceous period. Fossils have been found in the United States and possible specimens in Belgium and Africa. A well-preserved specimen of Platecarpus shows that it fed on moderate-sized fish, and it has been hypothesized to have fed on squid, and ammonites as well. Like other mosasaurs, it was initially thought to have swum in an eel-like fashion, although another study suggests that it swam more like modern sharks. An exceptionally well-preserved specimen of P. tympaniticus known as LACM 128319 shows skin impressions, pigments around the nostrils, bronchial tubes, and the presence of a high-profile tail fluke, showing that it and other mosasaurs did not necessarily have an eel-like swimming method, but were more powerful, fast swimmers. It is held in the Natural History Museum of Los Angeles County. Isotopic analysis on teeth specimens has suggested that this genus and Clidastes may have entered freshwater occasionally, just like modern sea snakes.
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