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出典:『Wikipedia』 (2010/08/12 17:48 UTC 版)

英語による解説

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Carinodens (meaning 'keel teeth') is a genus of mosasaur. It was named in 1969 as a replacement for Compressidens, which was already in use for a mollusk. Measuring approximately 3.5 metres (11 ft) in length, it is one of the smallest known mosasaurs. It is widely considered a sister taxon to Globidens. It also had round, blunt teeth for crushing primitive clams and oysters. Most cranial elements have been found in The Netherlands. The only postcranial material was recovered from latest Maastrichtian deposits of Jordan. The new material, assigned to a new species of Carinodens by Kaddumi (2009), is represented by an almost complete skull with at least 24 teeth still occupying their natural locations, complete neck vertebral series as well as several back vertebrae, and front paddles. In addition to the dentary, maxillary, and premaxillary teeth, several small pterygoid teeth are also preserved in this new material. Based on the remarkable dental heterodonty exhibited in the new species from Jordan, several new prey items may be postulated for Carinodens. Skeletal morphologies suggest that at least some Carinodens species were lightweight fast swimming slender mosasaurs with a streamlined body equipped with strong vision and advanced maneuvering capabilities, attributes that would act as natural defenses against the much larger and fierce predators that shared with it the same paleoenvironment.