Aegyptosaurus

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Aegyptosaurus
Temporal occurrence
Upper Cretaceous ( Cenomanium )
100.5 to 93.9 million years
Locations
Systematics
Dinosaur (dinosauria)
Lizard dinosaur (Saurischia)
Sauropods (Sauropoda)
Macronaria
Titanosaurs (Titanosauria)
Aegyptosaurus
Scientific name
Aegyptosaurus
Stromer , 1932
Art
  • Aegyptosaurus baharijensis

Aegyptosaurus is a genus of sauropod dinosaurs from the Titanosauria group . Fossils come from the early Upper Cretaceous North Africa.

Aegyptosaurus was already in 1932 by the German paleontologist Ernst Stromer of Reichenbach reference to a fragmentary skeleton described selected from the Bahariya Oasis ( Bahariya Formation ) in Egypt originates. The only species is Aegyptosaurus baharijensis . This skeleton has since been kept in Munich and was lost in an air raid on April 24 and 25, 1944 in the Museum Alte Akademie during World War II .

features

Aegyptosaurus was a medium-sized sauropod with an estimated length of 16 meters and a weight of about 10 tons. The exact differentiation from other genera is difficult because the bones are no longer available for new investigations.

The only other sauropod from the Bahariya Formation is the Paralititan , described in 2001 , which can, however , be distinguished from Aegyptosaurus by some features : Aegyptosaurus was significantly smaller than Paralititan , for example, the humerus measures only 59% of the length of the upper arm bone of Paralititan . According to Ernst Stromer's observations, the anterior caudal vertebrae of Aegyptosaurus had lateral cavities (pleurocoels), in contrast to Paralititan . Further differences between these genera can be found in the morphology of the shoulder blade and humerus.

The anterior and middle caudal vertebrae appear to have been procoel (concave on the front) - a feature of more modern (more derivative) titanosaurs.

Systematics

The systematic position within the Titanosauria is unclear. Upchurch and colleagues (2004) consider Aegyptosaurus to be a more native titanosaur and classify it outside of the Lithostrotia , a group to which all more modern titanosaurs are assigned. Curry Rogers (2005) classifies Aegyptosaurus as the original representative within Saltasauridae , together with genera such as Opisthocoelicaudia , Saltasaurus , Nemegtosaurus and Rapetosaurus .

Find, research history and naming

Ernst Stromer researched the Bahariya oasis at the beginning of the 20th century and described a diverse fossil vertebrate fauna. In addition to the remains of the Aegyptosaurus , he found, for example, the theropods Spinosaurus , Carcharodontosaurus and Bahariasaurus . Stromer's collection, including the Aegyptosaurus bones, was kept in the Old Academy in Munich (then the seat of the Bavarian State Collection for Paleontology and Historical Geology ) and was largely lost in the air raid on Munich in 1944. The fragmentary skeleton ( holotype , copy number BSP 1912 VIII 61) of Aegyptosaurus consisted of a partially preserved shoulder blade , nine leg bones and three caudal vertebrae . These remains probably came from the early Upper Cretaceous ( Cenomanium ).

The name Aegyptosaurus is derived from the Latin Aegypto and the Greek saura and means something like "Egyptian lizard". The species name baharijensis refers to the Baharija oasis, where the skeleton was found.

In addition to the holotype specimen, Ernst Stromer described a few other sauropod fossils from the Baharija oasis and temporarily assigned them to Aegyptosaurus as well. These findings include an indeterminable vertebra (BSP 1912 VIII 66), two possible tail vertebrae (BSP 1912 VIII 67) and a procoel caudal vertebra (BSP 1912 VIII 65). Since two sauropods from the Baharija fauna have been known with the discovery of Paralititan , these remains have to be classified as Sauropoda of unexplained assignment ( incertae sedis ), since it is not clear to which of the two genera they belonged. Lapparent (1960) assigned three further fragmentary finds from Niger to this genus .

literature

  • Ernst Stromer : Results of Prof. E. Stromer's research trips in the deserts of Egypt. Division 2: vertebrate remains of the Baharîje stage (lowest Cenoman). Vol. 11: Sauropoda (= treatises of the Bavarian Academy of Sciences. Mathematical and Natural Science Department. NF Vol. 10, ISSN  0005-6995 ). Publishing house of the Bavarian Academy of Sciences, Munich 1932.

Individual evidence

  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. 205, online .
  2. ^ A b William Nothdurft, Josh Smith: The Lost Dinosaurs of Egypt. Paperback edition. Random House, New York NY 2003, ISBN 0-375-75979-4 , pp. 19-20.
  3. ↑ 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 , p. 398.
  4. ^ A b Joshua B. Smith, Matthew C. Lamanna, Kenneth J. Lacovara, Peter Dodson , Jennifer R. Smith, Jason C. Poole, Robert Giegengack, Yousry Attia: A Giant sauropod dinosaur from an Upper Cretaceous mangrove deposit in Egypt. In: Science . Vol. 292, No. 5522, 2001, pp. 1704-1706, doi : 10.1126 / science.1060561 .
  5. ↑ Louis L. Jacobs, Dale A. Winkler, William R. Downs, Elizabeth M. Gomani: New Material of an early cretaceous Titanosaurid Sauropod Dinosaur from Malawi. In: Palaeontology. Vol. 36, No. 3, 1993, pp. 523-534, digitized version (PDF; 1.05 MB) ( Memento from December 8, 2015 in the Internet Archive ).
  6. ^ A b 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.
  7. ↑ 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 .
  8. ↑ Don Lessem , Donald F. Glut : The Dinosaur Society's Dinosaur Encyclopedia. Random House, New York NY et al. 1993, ISBN 0-679-41770-2 , p. 7.
  9. ↑ Aegyptosaurus . In: The Paleobiology Database. Retrieved August 27, 2014 .
  10. ^ Albert F. de Lapparent: Les dinosauriens du "continental intercalaire" du Sahara central (= Mémoires de la Société Géologique de France. NS Vol. 39, No. 88A, ISSN  0369-2027 ). Société Géologique de France, Paris 1960.

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