Saltasaurus
| Saltasaurus | ||||||||||||
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Artistic reconstruction of the life of Saltasaurus loricatus |
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| Temporal occurrence | ||||||||||||
| Upper Cretaceous (late Campanium to early Maastrichtian ) | ||||||||||||
| 76.4 to 69.9 million years | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Saltasaurus | ||||||||||||
| Bonaparte & Powell , 1980 | ||||||||||||
| Art | ||||||||||||
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Saltasaurus is a genus of sauropod dinosaur from the Titanosauria group that lived in the late Upper Cretaceous South America. The only recognized species is Saltasaurus loricatus .
So far, parts of the skeleton of at least five individuals are known, including cranial, vertebral and leg boils. These fossils come from the layers of the Lecho Formation in the Argentine province of Salta and can be dated from the late Campanian to early Maastrichtian .
Saltasaurus showed armor made of osteoderms (skin bone plates), which consisted of large plates and mosaic-like surfaces of small bones. It is one of the most derived (advanced) titanosaurs and is classified within the subfamily Saltasaurinae and the family Saltasauridae .
features
With a length of twelve meters, Saltasaurus was one of the smaller sauropods. He was the first sauropod in which osteoderms could be proven beyond doubt. These cutaneous bone plates were found in direct association with the remains of various individuals. Two types of osteoderms can be distinguished: The first type is characterized by oval, decimeter-sized plates, some of which were provided with combs or spikes. The second type, the “mosaic type”, is present in the form of mosaic-like surfaces made up of small bones about 10 millimeters in size.
The skeleton has only been handed down very incompletely. However, related genera show a shorter tail than other sauropods, a more flexible spine and a skull with an elongated snout and thin tooth crowns , which resembles those of the Diplodocidae . Saltasaurus probably followed a similar blueprint. The fore and hind legs of Saltasaurus and other titanosaurs did not stand vertically under the body, as with other sauropods, but were slightly bent outwards. For example, the outwardly angled thigh bone of Saltasaurus was more than twice as wide when viewed from the front than when viewed from the side, which counteracted the increased bending moment caused by the wider leg position.
Various anatomical features differentiate Saltasaurus from other genera ( autapomorphies ): For example, the front caudal vertebrae were about twice as wide as they were high. The ribs of the anterior caudal vertebrae were robust and thickened at their lower end. The front and middle cervical vertebrae also show a crest on the underside of the vertebral bodies.
Paleobiology
A large nesting site for titanosaurs , the Auca Mahuevo site, was discovered in 1997 by Luis Chiappe and his team in Patagonia . The rounded eggs contained complete fossil embryos with skin prints. Admittedly, these remains cannot be ascribed to any known genus of titanosaurs; however, the large number of clutches in a single location suggests that at least some titanosaurs have formed large nesting colonies.
Systematics
Saltasaurus is often within the titanosaur within a saltasauridae mentioned family belongs. Within this family, the two subfamilies Opisthocoelicaudiinae (mainly Opisthocoelicaudia and Alamosaurus ) and Saltasaurinae (mainly Saltasaurus , Neuquensaurus and Rocasaurus ) are led. While the relationships within the Titanosauria are highly controversial to this day, practically all studies consistently state that Saltasaurus is the most derived or one of the most derived (most advanced) titanosaur genera.
Finds, research history and naming
Saltasaurus was described scientifically for the first time in 1980 by José Bonaparte and Jaime Powell with the type species Saltasaurus loricatus . The name Saltasaurus ( Salta , gr. Sauros "lizard") is named after the Argentine province of Salta in northwest Argentina , where the first fossils were discovered.
McIntosh (1990) considered Titanosaurus robustus and Titanosaurus australis as further species of Saltasaurus ( Saltasaurus robustus and Saltasaurus australis ). These two Saltasaurus species are no longer recognized today. While Titanosaurus australis is considered to be an independent genus ( Neuquensaurus ), Titanosaurus robustus is considered a noun dubium (dubious name), which could be identical to Neuquensaurus or Saltasaurus .
Web links
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. 213, online .
- ^ A b c 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.
- ↑ Thomas R. Holtz Jr .: Supplementary Information. to: Thomas R. Holtz Jr .: Dinosaurs. The most complete, up-to-date Encyclopedia for Dinosaur Lovers of all ages. Random House, New York NY 2007, ISBN 978-0-375-82419-7 , online (PDF; 184.08 kB) .
- ↑ Ignacio A. Cerda, Jaime E. Powell: Dermal armor histology of Saltasaurus loricatus, an Upper Cretaceous sauropod dinosaur from Northwest Argentina. In: Acta Palaeontologica Polonica. Vol. 55, No. 3, 2010, ISSN 0567-7920 , pp. 389-398, doi : 10.4202 / app.2009.1101 .
- ↑ Michael D. D'Emic, Jeffrey A. Wilson, Sankar Chatterjee: The titanosaur (Dinosauria: Sauropoda) osteoderm record: review and first definitive specimen from India. In: Journal of Vertebrate Paleontology. Vol. 29, No. 1, 2009, ISSN 0272-4634 , pp. 165-177, doi : 10.1671 / 039.029.0131 .
- ↑ Kristina Curry Rogers: Titanosauria: A Phylogenetic Overview. In: Kristina Curry A. Rogers, Jeffrey A. Wilson (Eds.): The Sauropods. Evolution and Paleobiology. University of California Press, Berkeley CA et al. 2005, ISBN 0-520-24623-3 , pp. 50-103, doi : 10.1525 / california / 9780520246232.003.0003 .
- ↑ a b Jeffrey A. Wilson: An Overview of Titanosaur Evolution and Phylogeny. In: Fidel Torcida Fernández-Baldor, Pedro Huerta Hurtado (eds.): Actas de las III Jornadas Internacionales sobre Paleontología de Dinosaurios y Su Entorno. = Proceedings of the 3rd International Symposium about Paleontology of Dinosaurs and their Environment Paleontología de dinosaurios y su entorno. Salas de los Infantes (Burgos, España), 16 al 18 de septiembre de 2004. Colectivo arqueológico-paleontológico de Salas, Salas de los Infantes (Burgos, España) 2006, ISBN 84-8181-227-7 , pp. 169-190 .
- ↑ Jeffrey A. Wilson, Matthew T. Carrano: Titanosaurs and the Origin of "Wide-Gauge" Trackways: A Biomechanical and Systematic Perspective on Sauropod Locomotion. In: Paleobiology. Vol. 25, No. 2, 1999, ISSN 0094-8373 , pp. 252-267.
- ↑ Luis M. Chiappe , Frankie Jackson, Rodolfo A. Coria , Lowell Dingus : Nesting Titanosaurs from Auca Mahuevo and Adjacent Sites: Understanding Sauropod Reproductive Behavior and Embryonic Development. In: Kristina Curry A. Rogers, Jeffrey A. Wilson (Eds.): The Sauropods. Evolution and Paleobiology. University of California Press, Berkeley CA et al. 2005, ISBN 0-520-24623-3 , pp. 285-302, doi : 10.1525 / california / 9780520246232.003.0011 .
- ↑ José F. Bonaparte , Jaime E. Powell: A continental assemblage of tetrapods from the Upper Cretaceous beds of El Brete, northwestern Argentina (Sauropoda-Coelurosauria-Carnosauria-Aves). In: Mémoires de la Société Géologique de France. NS Vol. 139, 1980, ISSN 0369-2027 , pp. 19-28.
- ↑ Ben Creisler: Dinosauria Translation and Pronunciation Guide ( Memento of October 13, 2011 in the Internet Archive )
- ↑ 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 .