Gondwanatitan

Gondwanatitan
Temporal occurrence
	Upper Cretaceous ( Campanium or Maastrichtium )
	83.6 to 66 million years
Locations
	Brazil , Bauru Group ( São Paulo );
Systematics
	Dinosaur (dinosauria)
	Lizard dinosaur (Saurischia)
	Sauropodomorpha
	Sauropoda
	Titanosaurs (Titanosauria)
	Gondwanatitan
Scientific name
	Gondwanatitan
	Kellner & Azevedo , 1999
Art
	Gondwanatitan faustoi;

Gondwanatitan is a genus of sauropod dinosaurs from the Titanosauria group thatlived in South Americaduring the Late Upper Cretaceous ( Campanium or Maastrichtian ).

So far, a fragmentary, skull-less skeleton is known that comes from the Bauru group in the Brazilian state of São Paulo . The only species is Gondwanatitan faustoi . Gondwanatitan is often classified within the Titanosauria together with the related Aeolosaurus in the Aeolosaurini group .

features

Gondwanatitan was a relatively small sauropod - so the skeleton found belonged to an animal about 6 to 7 meters long. Like all sauropods, it was a herbivore with a long neck and tail. Gondwanatitan can be distinguished from other titanosaurs by various features ( autapomorphies ): The anterior and middle caudal vertebrae were heart-shaped and the deltopectoral ridge of the humerus was very well developed and shaped differently. The shinbone (tibia) shows further autapomorphies , the upper, anterior articular surface of which is extended upwards (dorsally) and the cnemial ridge is only slightly curved laterally.

Systematics

The systematic position of this genus is controversial. The first descriptors state that Gondwanatitan must be classified within the Titanosauria. Within this group, this genus would neither belong to the Saltasaurinae ( Saltasaurus and Neuquensaurus ), nor to the very original forms such as Andesaurus and Malawisaurus . You notice that Gondwanatitan shares at least one common trait with Aeolosaurus : Thus the spinous processes of the anterior and middle caudal vertebrae were directed forward. Some paleontologists therefore classify Gondwanatitan together with Aeolosaurus in a separate group within the Titanosauria - the Aeolosaurini . Rinconsaurus is also occasionally classified within the Aeolosaurini . Upchurch and colleagues (2004) classify Aeolosaurus within the Lithostrotia (= Titanosauridae), a group that includes all advanced titanosaurs.

Research history, find and naming

The site is in the region of Álvares Machado in São Paulo. The first bones were discovered in 1983 by the farmer Yoshitoshi Myzobuchi, who informed the vertebrate paleontologist Fausto Luiz de Souza Cunha from the Museu Nacional in Rio de Janeiro . Fausto recognized that it was the remains of a titanosaur and organized excavations, which between 1984 and 1986 brought the fragmentary skeleton of Gondwanatitan and other vertebrate fossils to light. Only partially prepared, the skeleton has since been kept in the collection of the Museu Nacional do Rio de Janeiro without further investigation. It was not until September 1997 that researchers around Alexander Kellner and Sergio de Azevedo continued the preparation , which led to the description of the new genus in 1999. The name Gondwanatitan is made up of Gondwana , the southern supercontinent, and the titans of Greek mythology . The Artepitheth faustoi honors Fausto de Souza Conha, the former head of the Museu Nacional in Rio de Janeiro, who excavated the fossils.

The remains come from a layer of mudstone - fine-grained rock in the clay to silt range - which is part of a normal graded river deposit . Overlying conglomerates also contained the remains of turtles and crocodiles. The site belongs to the Adamantina Formation , a member of the Bauru group .

Gondwanatitan's fossils have been preserved to varying degrees. For example, while the humerus, shin and caudal vertebrae are well preserved, other bones were on the surface or damaged by vegetation. Many of the bones were in such poor condition that they could not be collected. All bones were surrounded by a layer of dark and hard layer of manganese oxide .

The skeleton ( holotype , copy number MN 4111-V) consists of some vertebrae (2 partially cervical vertebrae, 7 dorsal vertebrae, 6 sacral vertebrae, 24 caudal vertebrae and four vertebrae that cannot be assigned), the upper area of the shoulder blade (scapula), pelvic bones (the incomplete iliac bone ( Os ilium), pubic bones (ossa pubis) and ischia (ossa ischii)), both humerus bones, both shins, some ribs and various other bones that cannot be assigned.

supporting documents

Main source

Alexander WA Kellner, Sergio AK Azevedo: A new sauropod dinosaur (Titanosauria) from the Late Cretaceous of Brazil. In: Yukimitsu Tomida, Thomas H. Rich, Patricia Vickers-Rich: Proceedings of the Second Gondwanan Dinosaur Symposium. (Held at the National Science Museum in Tokyo on July 12-13, 1998) (= National Science Museum Monographs. No. 15, ISSN 1342-9574 ). National Science Museum, Tokyo 1999, pp. 111-142.

Individual evidence

^ Gregory S. Paul : The Princeton Field Guide To Dinosaurs. Princeton University Press, Princeton NJ et al. 2010, ISBN 978-0-691-13720-9 , p. 208, online ( memento of the original of July 13, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . @1@ 2

↑ Aldirene Costa Franco-Rosas, Leonardo Salgado , Claudio Fabián Rosas, Ismar de Souza Carvalho: Nuevos materiales de titanosaurios (Sauropoda) en el Cretacico Superior de Mato Grosso, Brazil. In: Revista Brasileira de Paleontologia. Vol. 7, No. 3, 2004, pp. 329–336, digital version (PDF; 2.29 MB) .

↑ ^a ^b Gabriel Casal, Rubén Martínez, Marcelo Luna, Juan C. Sciutto, Matthew Lamanna: Aeolosaurus colhuehuapensis sp. nov. (Sauropoda, Titanosauria) de la Formación Bajo Barreal, Cretácico superior de Argentina. In: Revista Brasileira de Paleontologia. Vol. 10, No. 1, 2007, pp. 53-62, digital version (PDF; 2.85 MB) .

^ Paul Upchurch , Paul M. Barrett , Peter Dodson : Sauropoda. In: David B. Weishampel , Peter Dodson, Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 259-324.

[1] Gregory S. Paul : The Princeton Field Guide To Dinosaurs. Princeton University Press, Princeton NJ et al. 2010, ISBN 978-0-691-13720-9 , p. 208, online ( memento of the original of July 13, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . @1@ 2

[2] Aldirene Costa Franco-Rosas, Leonardo Salgado , Claudio Fabián Rosas, Ismar de Souza Carvalho: Nuevos materiales de titanosaurios (Sauropoda) en el Cretacico Superior de Mato Grosso, Brazil. In: Revista Brasileira de Paleontologia. Vol. 7, No. 3, 2004, pp. 329–336, digital version (PDF; 2.29 MB) .

[casal_07-3] Gabriel Casal, Rubén Martínez, Marcelo Luna, Juan C. Sciutto, Matthew Lamanna: Aeolosaurus colhuehuapensis sp. nov. (Sauropoda, Titanosauria) de la Formación Bajo Barreal, Cretácico superior de Argentina. In: Revista Brasileira de Paleontologia. Vol. 10, No. 1, 2007, pp. 53-62, digital version (PDF; 2.85 MB) .

[dinosauria-4] Paul Upchurch , Paul M. Barrett , Peter Dodson : Sauropoda. In: David B. Weishampel , Peter Dodson, Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 259-324.