Alvarezsaurus
| Alvarezsaurus | ||||||||||||
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Alvarezsaurus , skeleton reconstruction |
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| Temporal occurrence | ||||||||||||
| Upper Cretaceous ( Turonium to Santonium ) | ||||||||||||
| 93.9 to 83.6 million years | ||||||||||||
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| Scientific name | ||||||||||||
| Alvarezsaurus | ||||||||||||
| Bonaparte , 1991 |
Alvarezsaurus ("Alvarezechse") is a genus of theropod dinosaur from the Upper Cretaceous ( Turonium to Santonium ) of South America. Its fossils are dated to an age of approximately 94 to 86 million years and were found in Argentina. Alvarezsaurus was a basal member of the Alvarezsauridae family named after him .
A skeleton without a skull was found in 1987 in the Bajo de la Carpa formation on the banks of the Río Colorado , and scientifically described in 1991 by the paleontologist José Fernando Bonaparte . The genus was named after the Argentine historian Gregorio Alvarez .
Alvarezsaurus was likely a fast runner and had a tail that took up about two-thirds of the animal's total length. Alvarezsaurus was probably about 2 meters long and weighed about 20 kilograms. Presumably he ate insects . He probably wore plumage and was probably endothermic .
Alvarezsaurus was a basal Alvarezsauridae . The hand was typical of this group; they had only one claw. Cladogram according to Xu et al. (2011):
| Alvarezsauroidea |
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literature
- José F. Bonaparte : Los vertebrados fósiles de la Formación Rio Colorado, de la ciudad de Neuquen y cercanías, Cretácico Superior, Argentina. In: Revista del Museo Argentino de Ciencias Naturales Bernardino Rivadavia e Instituto Nacional de Investigación de las Ciencias Naturales. Paleontología. Vol. 4, No. 3, 1991, ISSN 0524-9511 , pp. 17-123.
Individual evidence
- ↑ Xing Xu , Corwin Sullivan, Michael Pittman, Jonah N. Choiniere, David Hone, Paul Upchurch , Qingwei Tan, Dong Xiao, Lin Tan, Fenglu Han: A monodactyl nonavian dinosaur and the complex evolution of the alvarezsauroid hand 2011 A monodactyl nonavian dinosaur and the complex evolution of the alvarezsauroid hand . In: Proceedings of the National Academy of Sciences of the United States of America . Vol. 108 No. 6, 2011, pp. 2338-2342, doi : 10.1073 / pnas.1011052108 .