| Simosaurus Temporal range: Middle to Late Triassic | |
|---|---|
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| A skeleton of Simosaurus | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | †Sauropterygia |
| Order: | †Nothosauria |
| Family: | †Simosauridae |
| Genus: | †Simosaurus Meyer, 1842 |
| Species: | †S. gaillardoti |
Simosaurus is an extinct genus of sauropterygian reptile in the order Nothosauria. Its fossils have been found in Middle and Upper Triassic of Europe (France, Germany, Italy) and Asia (Israel, Saudi Arabia). The type and only species is Simosaurus gaillardoti, firstly described from the Ladinian limestone of Lunéville, France, by Meyer in 1842.[1] Like all nothosaurs, it was a carnivore aquatic reptile that lived in shallow waters.[2]
The type specimen, a skull, was collected from the Blainville, Lunéville, France, and now lost. later, other specimens were found in Hoheneck (Germany), Dogna (Italy)[3] and other localities.
Description[]
Simosaurus was relatively large nothosaur of 3-4 m in body length. Due to the findings of specimens of individuals of different ages, it was possible to develop models of their growth. The cubs gained 44-69 g of mass per day and by the age of 10-20 years their weight ranged from 113 to 129 kg. A distinctive feature of Simosaurus is its relatively short, flat skull with broad lateral teeth. Most likely, the animal could chew through strong shells and fed on holostean fish and ammonites. The structure of the limb bones indicates that this animal swam less effective than its close relatives.[2] This feature probably confirms that Simosaurus hunted slow animals with strong shells. This type of diet is called durophagy. Its flat limbs did not allow it to move well on land, but it is possible that Simosaurus climbed ashore to lay eggs.
Paleoecology[]
As many other nothosaurs, Simosaurus lived along the western coasts of the Tethys Ocean, which jutted into the central part of Pangea from the eastern side. The vast shallow areas contained numerous fish that Simosaurus could prey on. Marine reptiles of the time included placodonts, ichthyosaurs and other nothosaurs.
In the Middle Triassic Gevanim Formation of Israel, placodonts (Psephoderma, Psephosauriscus) and Saurichthys were found alongside the Simosaurus.[4] In Tiefenbach, Germany, Simosaurus was found in same strata as Placodus, another durophagous sea reptile.[5] An indeterminate species of Simosaurus had been reported from the Lower Lias of Bourgogne-Franche-Comté, France, which corresponds to the Rhaetian age of the Triassic. Termatosaurus, a predatory reptile of uncertain taxonomy, is also found there.[6]
References[]
- ↑ H. von Meyer, (1842). "Simosaurus, die Stumpfschnauze, ein Saurier aus dem Muschelkalke von Luneville". Neues Jahrbuch für Mineralogie, Geognosie, Geologie und Petrefakten-Kunde 1842: pp. 184-197.
- ↑ 2.0 2.1 Klein N., Griebeler E. M. (2016). "Bone histology, microanatomy, and growth of the nothosauroid Simosaurus gaillardoti (Sauropterygia) from the Upper Muschelkalk of southern Germany/Baden-Württemberg". Comptes Rendus Palevol 15 (1-2): pp. 142-162. DOI:10.1016/j.crpv.2015.02.009
- ↑ F. M. Dalla Vecchia (2008). "First record of Simosaurus (Sauropterygia, Nothosauroidea) from the Carnian (Late Triassic) of Italy". Rivista Italiana di Paleontologia e Stratigrafia 114 (2): pp. 273-285.
- ↑ M. Martin, G. Cuny, J. M. Mazin (1991). "Rostres de Saurichthys (Saurichthyiformes, Saurichthyidae) en trois dimensions dans le Trias Moyen d'Israël". Geobios 24: pp. 183-186.
- ↑ O. Rieppel (1994). "The braincases of Simosaurus and Nothosaurus: monophyly of the Nothosauridae (Reptilia: Sauropterygia)". Journal of Vertebrate Paleontology 14 (1): pp. 9-23.
- ↑ M. J. Henry. 1876. L'Infralias dans la Franche-Comté. Mémoires de la Société d'Émulation du Doubs, 4e série 10: pp. 287-486