Trigonosaurus

• Brazil, Minas Gerais (Marília Formation)

• Trigonosaurus pricei

Trigonosaurus is a genus of sauropod dinosaur from the group of Titanosauria that lived during the Late Cretaceous ( Maastrichtian ) in what is now South America.

So far, two very fragmentary skeletons are known to originate from the Marília Formation in the Brazilian state of Minas Gerais. More Titanosaurier this formation include Uberabatitan, Baurutitan and Aeolosaurus.

Features

Like all sauropods, it was a herbivore with a long neck and tail. The holotype specimen is estimated to have a length of about 9.5 meters. Compared to the contemporary Uberabatitan Trigonosaurus was built smaller and less robust.

From related genera is Trigonosaurus can differentiate to the vertebrae by a combination of diagnostic features: For example, the cervical vertebrae for example, were extended and had low spinous processes and a concave ventral edge. The middle back vertebrae were also extended, the spinous processes are heavily tilted forward. The prezygapophyses the tail vertebrae were extended forward and showed wide joint surfaces. The bonding surfaces of Hämalbögen are highly developed from the third vertebrae of the tail.

System

The relationships of this genus within the Titanosauria are unclear. However, it seems neither to the abgeleitetsten ( modern ) titanosaurs, the Saltasaurinae, nor on the basal ( primitive ) Titanosauria to have heard. Salgado, Coria and Calvo (1997) see a closer relationship with Opisthocoelicaudia, but this is doubted Campos and colleagues ( 2005). Campos and colleagues, however, see some similarities with the Aeolosaurini ( Aeolosaurus and Gondwana titanium); then the vertebral arches are further forne on the vertebral bodies, while the spinous processes were directed obliquely forward.

Fund, history of discovery and naming

The two skeletal fragments originate from the Caieira locality, a disused quarry about two kilometers north of Peirópolis near Uberaba. The fossils are of fine to medium -grained white to yellow sandstones belonging to the Marília Formation ( Serra da galga Members ), a formation of the Bauru Group. This formation is dated to the Maastrichtian, the last stage of the Upper Cretaceous.

The holotype specimen ( specimen number MCT 1488 -R ) consists of five cervical vertebrae, ten vertebrae, the sacrum and the left iliac bone ( ilium ). The vertebrae and the last cervical vertebra were when they were discovered in the anatomical network. The second copy ( para-type, copy number MCT 1719 -R ) consists of ten caudal vertebrae, which were indeed found in isolation, but probably belonged to a single individual because of their uniform size and morphology. It is possible that both copies to a single individual. The fossils are preserved in the Museu de Ciências da Terra.

The fossils were discovered by Llewellyn Ivor Price, and since then by various researchers investigated ( Powell, 1987; Campos and Kellner, 1999). They were taken as Peirópolis Series B, but not officially named. Only Diogenes de Almeida Campos and colleagues published in 2005 a comprehensive description and named the new genus Trigonosaurus pricei. The name Trigonosaurus ( gr TRIGONOS - " Triangle", Portuguese " triângulo "; saura - " lizard" ) has the Triângulo Mineiro, a region in Minas 've Traveled, from the date the fossils. The second part of Artnames, pricei honors Llewellyn Ivor Price, an eminent paleontologist and discoverer of the skeletons.

Documents

Main source

• D. d A. Campos, AWA Kellner, RJ Bertini, RM Santucci, 2005: On a titanosaurid ( Dinosauria, Sauropoda ) vertebral column from the Bauru Group, Late Cretaceous of Brazil. In: Arquivos do Museu Nacional, Rio de Janeiro. Volume 63, number 3, pages 565-593.