Кейінгі Юра кезеңінің Цератозавр тұқымдас динозавры - Элафрозавр

Ceratosaurian theropod dinosaur genus from the Late Jurassic Period

Elaphrosaurus (/ɛ/,/l//ɑː//f//r//oʊ/'/s//ɔːr//ə//s/ elAHfrohSORəs) is a genus of ceratosaurian theropod dinosaur that lived approximately 154 to 150 million years ago during the Late Jurassic Period in what is now Tanzania in Africa. Elaphrosaurus was a medium sized but lightly built member of the group that could grow up to long. Morphologically, this dinosaur is significant in two ways. Firstly, it has a relatively long body but is very shallow chested for a theropod of its size. Secondly, it has very short hindlimbs in comparison with its body. Phylogenetic analyses indicate that this genus is likely a ceratosaur. Earlier suggestions that it is a late surviving coelophysoid have been examined but generally dismissed. Elaphrosaurus is currently believed to be a very close relative of Limusaurus, an unusual beaked ceratosaurian which may have been either herbivorous or omnivorous.

The type specimen of Elaphrosaurus bambergi HMN Gr. S. 38–44 was recovered in the Middle Dinosaur Member of the Tendaguru Formation of Lindi Region in Tanzania. The specimen was collected by Werner Janensch, I. Salim, H. Reck, and Parkinson in 1910 in gray, green, red, sandy marl that was deposited during the Kimmeridgian stage of the Jurassic period, approximately 157 to 152 million years ago. This specimen is housed in the collection of the Natural History Museum of Berlin, Germany. Elaphrosaurus was described and named by Werner Janensch in 1920 and the type species is Elaphrosaurus bambergi. The genus name Elaphrosaurus is derived from the Greek words elaphros (ελαφρός) meaning "light to bear" as in "light footed", a reference to its presumed high running speed and "sauros" ([[wikt:σαῦρος) meaning "lizard"; thus, "light footed lizard". The specific name honours the industrialist Paul Bamberg for his financial support of the Tendagaru expeditions. Few theropod skeletons have been found, most discoveries being fragments. Dinosaur footprints from the Niger Republic and from Beit Zayit were attributed to Elaphrosaurus. This assignment is considered inconclusive.

Paul (1988) noted that Elaphrosaurus bambergi was too small to prey on the sauropods and stegosaurs present in its paleoenvironment, and instead, it likely hunted the small and swift ornithopod herbivores. However, newer studies support the idea that Elaphrosaurus was a herbivore or omnivore, owing to its close relation with Limusaurus and a neck which is much less flexible than those characteristic of carnivorous theropods.

Studies suggest that the paleoenvironment of the Tendaguru Formation was a marginal marine environment with both non marine faunal and floral content. The Middle Dinosaur Member of the Tendaguru Formation has yielded the sauropods Giraffatitan, Australodocus, Janenschia, Tornieria and Dicraeosaurus, theropods similar to Allosaurus and Ceratosaurus, the carcharodontosaurid Veterupristisaurus, the stegosaurid Kentrosaurus and the iguanodontian Dysalotosaurus. Dinosaurs shared this paleoenvironment with pterosaurs like Pterodactylus and Rhamphorhynchus, as well as with early mammals.