Ekrixinatosaurus

Artistic representation of live Ekrixinatosaurus novasi

  • Ekrixinatosaurus novasi

Ekrixinatosaurus is a genus theropod dinosaur from the group of Abelisauridae. She is known by a single fragmentary skeleton that was found in the Argentine province of Neuquén and the Upper Cretaceous ( Cenomanian ) is dated. It was a very large, bipedal running carnivores, like the closely related genera Skorpiovenator and Carnotaurus by a short and high skull stands out. Ekrixinatosaurus was described in 2004 by researchers at Jorge Calvo with the single species E. novasi scientifically.

The skeleton was accidentally uncovered during blasting for the construction of a gas pipeline. The name Ekrixinatosaurus ( gr ekrixi - "explosion", nato - "born", saurus - "lizard "), which means something like " an explosion born lizard", in reference to this circumstance. The second part of the species name, novasi honors Fernando Novas, a paleontologist who has made ​​an outstanding contribution in the study of Abelisauriden.

Features

Calvo and colleagues ( 2004) estimate the body length of the only known skeleton on 7-8 m. A younger, focused on the body proportions of this genre study of Juárez Valieri and colleagues (2011 ), however, estimated the body length to 10 to 11 meters, which Ekrixinatosaurus one of the largest or even the largest known representative of the Abelisauridae would have been. Ekrixinatosaurus was characterized by a high and short skull. There was an overall relatively bulky and stocky built Abelisauriden; so especially the shinbone ( tibia) and the thigh bone ( femur) were relatively short and robust.

System

The preliminary cladistic analysis of Calvo and colleagues (2004 ) summarizes Ekrixinatosaurus, Majungatholus, Carnotaurus and Aucasaurus together to an unnamed group - Ilokelesia forms the sister taxon of this group. Researchers led by Juan Canale (2008 ) summarize Ekrixinatosaurus, Aucasaurus, Carnotaurus, and Ilokelesia Skorpiovenator together in the new group Brachyrostra; Representatives of this group are characterized by relatively short skull. These researchers see Ekrixinatosaurus as a sister genus of Skorpiovenator.

Rugops

Abelisaurus

Majungasaurus

Carnotaurus

Aucasaurus

Ilokelesia

Skorpiovenator

Ekrixinatosaurus

Paleoecology

The skeleton comes from the Candeleros Formation, which is dated to the Cenomanian, the oldest stage of the Upper Cretaceous. The Abelisauridae showed from the Turonian following a skyrocketing biodiversity, possibly with the presumed extinction of Carcharodontosauridae at this time are connected - another group of very large theropods. According to a hypothesis is particularly great representative of Abelisauridae could develop only after the disappearance of the Carcharodontosauridae. Ekrixinatosaurus seem to refute this hypothesis, since these species shared their habitat with the huge Carcharodontosauriden Giganotosaurus. Speculate Rubén and colleagues ( 2011) that both may be occupied different ecological niches Großtheropoden; so could one of these predators have been an active predator, while the other may have been a specialized scavengers. The Body of Ekrixinatosaurus would have a slow, sturdy animal that would have been able to assert itself on cadavers against other predators.

Discovery

The only known skeleton ( holotype, MUCPv294 ) consists of a few skull bones ( maxilla, Basicranium, dental and teeth), from some vertebrae and Hämalbögen ( cervical, dorsal, sacral, and caudal vertebrae ), ribs, pelvic bone ( ilium, pubis, an ischial fragment) and leg bones ( femur, tibia, astragalus, calcaneum, a fibula fragment, metatarsals, phalanges and a claw). Arms, most of the cervical vertebrae and the skull are missing.

The skeleton has been found in well-preserved but disarticulated state ( the bones were no longer in their original anatomical position). The site is located about 34 km north- west of ANELO.

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