Aetosauria
Aetosauria | ||||||||||||
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Desmatosuchus spurensis in size comparison with a human. |
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Temporal occurrence | ||||||||||||
Upper Triassic | ||||||||||||
228 to 203.6 million years | ||||||||||||
Locations | ||||||||||||
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Aetosauria | ||||||||||||
Lydekker , 1889 |
The aetosaurs ("eagle lizards"), also known as Stagonolepididae , are a taxon of extinct, medium-sized, herbivorous and heavily armored archosaurs from the late Triassic .
Aetosauria fossil remains have been found in Europe , including in Baden-Württemberg ( Murrhardt and Weißer Steinbruch ), Greenland , the United States , Argentina , Brazil , Morocco and Madagascar . The most important sites are the Chinle Formation in the USA, where Desmatosuchus was found, and Elgin in Scotland , where Aetosaurus and Stagonolepis come from. Usually only the bone plates of the armor are preserved as fossils.
The aetosaurs became extinct at the end of the Triassic (203.6 million years ago) along with many other land-based vertebrates. Trace fossils that are assigned to the aetosaurs could point to a survival of the taxon as far as the Jurassic or even the Lower Cretaceous .
features
The head of the aetosaur is small in relation to its body. It's blunted at the front and perhaps served to look for rhizomes and roots in the ground like pigs . The small teeth were leaf-shaped and typical of herbivores.
Aetosaurs had crocodile-like, massive bodies armored with large, square plates. The plates were probably covered with horn. The tail was long, similar to that of crocodiles . The back legs of the aetosaurs were longer than the front legs. Some forms, like Desmatosuchus, were additionally protected by long spikes on the flanks. Aetosaurs were one to three meters long, the largest species up to five meters.
Internal system
Cladogram according to Parker et al. (2008):
Aetosauria |
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swell
literature
- Robert L. Carroll : Paleontology and Evolution of the Vertebrates. Thieme, Stuttgart et al. 1993, ISBN 3-13-774401-6 .
Individual evidence
- ↑ The Paleobiology Database Batrachopodidae
- ^ William G. Parker, Michelle R. Stocker, Randall B. Irmis: A new desmatosuchine aetosaur (Archosauria; Suchia) from the Upper Triassic Tecovas Formation (Dockum Group) of Texas. In: Journal of Vertebrate Paleontology. Vol. 28, No. 2, 2008, ISSN 0272-4634 , pp. 692-701, doi : 10.1671 / 0272-4634 (2008) 28 [692: ANDAAS] 2.0.CO; 2 .
Web links
- University of California Museum of Paleontology: Introduction to the Aetosauria
- The Paleobiology Database: Aetosauria
- Palæos: Aetosauridae
- Aetosauria Translation and Pronunciation Guide ( Memento of October 13, 2011 in the Internet Archive )