Argyrosaurus

Argyrosaurus
Temporal occurrence
	Upper Cretaceous ( Campanium or Maastrichtium )
	83.6 to 66 million years
Locations
	Argentina;
Systematics
	Dinosaur (dinosauria)
	Sauropodomorpha
	Sauropoda
	Macronaria
	Titanosaurs (Titanosauria)
	Argyrosaurus
Scientific name
	Argyrosaurus
	Lydekker , 1893
Art
	Argyrosaurus superbus;

Argyrosaurus is a genus of sauropod dinosaur from the Titanosauria group . Fossils of this genus come from the Upper Cretaceous ( Campanium or Maastrichtian ) of Argentina .

Argyrosaurus was first scientifically described in 1893 by Richard Lydekker using a foreleg , the only species being Argyrosaurus superbus . Other bone fragments that were added to this genus come in particular from the Bajo Barreal Formation . The name Argyrosaurus ( Greek argyros - "silver", Greek saura - "lizard") means something like "silver lizard" and refers to the country Argentina ("land of silver"), where the fossils were found.

features

Argyrosaurus was a large titanosaur. It can be distinguished from other genera by particularly high and short vertebral arches . Consisting of Elle (ulna) and spoke existing (radius) lower leg was robust, the metacarpal bones were as with other representatives of the macronaria long. The upper arm bone (humerus) shows a rectangular upper end, similar to that of the advanced (derived) titanosaurs Saltasaurus and Opisthocoelicaudia . An important feature that confirms the classification within the Titanosauria ( synapomorphism ) is a pronounced bone spur at the upper end of the ulna ( olecranon ).

Research history and validity of the genus

Richard Lydekker described Argyrosaurus in 1893 on the basis of an articulated front leg including a hand skeleton, which was discovered in the area of the Río Chubuts . In his first description, he assigned two more finds from other sites to this genus. According to Lydekker, these finds - a thigh bone (femur) from the Río Senguerr and two large caudal vertebrae from Santa Cruz - were similar in color and mineral composition, but the assignment of these finds to Argyrosaurus could not be confirmed by more recent studies. Powell (1986) and Bonaparte (1996) ascribed to this genus three dorsal vertebrae, three caudal vertebrae, a shoulder blade, a humerus, the ulna and radius of both forelegs, and the femur and tibia, which were found in the Bajo Barreal formation.

Upchurch and colleagues (2004) note that the status of the genus is in doubt. The only diagnostic features are found on the anterior caudal vertebrae, but they do not belong to the type series . So Argyrosaurus may have to be used as a noun dubium (dubious name) in the future.

Systematics

The systematic position of this genus within the Titanosauria is unclear. Most authors put Argyrosaurus among the Titanosauridae, a group of advanced Titanosauria. The name Titanosauridae is currently no longer recognized by many researchers - the name Lithostrotia has been suggested instead . Upchurch and colleagues (2004) classify Argyrosaurus outside of the Lithostrotia. Powell (1986) placed Argyrosaurus in its own subfamily, the Argyrosaurinae. The name Argyrosaurinae was used by some later authors (e.g. Bonaparte, 1996), but was not widely used.

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. 206, online .
↑ Ben Creisler: Dinosauria Translation and Pronunciation Guide. Archived from the original on November 20, 2010 ; accessed on August 28, 2014 .
↑ ^a ^b ^c ^d ^e ^f 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.
^ Richard Lydekker : Contributions to the study of the fossil vertebrates of Argentina. I. The dinosaurs of Patagonia. In: Anales del Museo de La Plata. Paleontología Argentina. Vol. 2, 1893, ZDB -ID 438149-x , pp. 1-14.
↑ ^a ^b Jeffrey A. Wilson, Paul Upchurch: A Revision of Titanosaurus Lydekker (Dinosauria - Sauropoda), the first dinosaur genus with a 'gondwanan' distribution. In: Journal of Systematic Palaeontology. Vol. 1, No. 3, 2003, ISSN 1477-2019 , pp. 125-160, doi : 10.1017 / S1477201903001044 .
^ Argyrosaurus . In: The Paleobiology Database. Retrieved October 19, 2010 .

[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. 206, online .

[2] Ben Creisler: Dinosauria Translation and Pronunciation Guide. Archived from the original on November 20, 2010 ; accessed on August 28, 2014 .

[dinosauria-3] ↑ ^a ^b ^c ^d ^e ^f 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.

[Lydekker-4] Richard Lydekker : Contributions to the study of the fossil vertebrates of Argentina. I. The dinosaurs of Patagonia. In: Anales del Museo de La Plata. Paleontología Argentina. Vol. 2, 1893, ZDB -ID 438149-x , pp. 1-14.

[titanosaurus-5] Jeffrey A. Wilson, Paul Upchurch: A Revision of Titanosaurus Lydekker (Dinosauria - Sauropoda), the first dinosaur genus with a 'gondwanan' distribution. In: Journal of Systematic Palaeontology. Vol. 1, No. 3, 2003, ISSN 1477-2019 , pp. 125-160, doi : 10.1017 / S1477201903001044 .

[6] Argyrosaurus . In: The Paleobiology Database. Retrieved October 19, 2010 .