Suevoleviathan

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Suevoleviathan
Suevoleviathan integer from the paleontological collection of the University of Tübingen

Suevoleviathan integer from the paleontological collection of the University of Tübingen

Temporal occurrence
Lower Jurassic ( Lower Toarcian )
182.7 to 174.1 million years
Locations
Systematics
Land vertebrates (Tetrapoda)
Sauropsida
Diapsida
Ichthyosaur (Ichthyosauria)
Suevoleviathanidae
Suevoleviathan
Scientific name
Suevoleviathan
Maisch , 1998
species
  • S. disinteger (von Huene, 1926) ( type species )
  • S. integer (Bronn, 1844)

Suevoleviathan ( Latin and Hebrew for "Swabian Leviathan" from 'Suevia' ( Swabia ) and ' Leviathan ' (biblical sea monster)) is a genus of ichthyosaurs from the Lower Jurassic of Baden-Württemberg .

features

The genus Suevoleviathan probably reached a total length of up to 6 meters. The skull is low and the eye sockets are rather medium in size compared to other ichthyosaurs . A secondary fossa of the dental and premaxillary fossa extends along the dental and premaxillary. The maxillary is short in the anterior prenarial area. The squamosum is large and forms most of the posterior cheek and extends to the ventral area of ​​the skull. The teeth are sturdy and short. The postflexural tail segment is unusually long and contributed to a large lunate caudal fin. The ribs are unicipital. The front fin has three primary finger rays, a postaxial and an accessory finger ray. In addition, the third ray is branched, so that another finger ray is added. Distally, the distance between the phalanx increases and gives the front fin a certain fan shape. The rear fin has three primary finger rays, but these are indented on the front. The basin consists of three non-merged elements. Furthermore, Motani gives the distally widened phalanges and the straight iliac bone has an anterior process.

Paleobiology

Suevoleviathan was a medium-sized ichthyosaur with a rather more flexible spine. This means that it was probably more agile than other ichthyosaurs, such as Ichthyosaurus . The relatively long tail fin (with many vertebral bodies) also suggests that it was not specialized in very high speeds. Since the vertebrae are slightly rounded in their entire length in the spine, this also indicates a more flexible mode of movement. According to Buchholtz, the kink of the tail is also less pronounced. The very large front fins were certainly not only used for changing direction, but also as a drive. The relatively large hind fins also indicate low speeds and their shared use when moving. They were very helpful, at least when changing direction. Overall, Suevoleviathan was one of the more agile ichthyosaur species that did not reach high speeds. Its body and teeth size, which is smaller than that of other ichthyosaurs, allowed it to hunt smaller prey.

Paleoecology

At the time of the Lower Jurassic , a diverse fauna of marine reptiles, cephalopods , fish and other animals occurred in the area of ​​southern Germany . Eurhinosaurus , Stenopterygius and Temnodontosaurus are just a few of the vertebrates found in this shallow sea. Plesiosaurs , pterosaurs and thalattosuchia are found in the same outcrops as suevoleviathan .

Systematics and taxonomy

The Suevoleviathanidae is closely related to the Leptonectidae and the Thunnosauria . The following cladogram shows the relationships between the Suevoleviathanidae and their sister groups.

 Parvipelvia  

 Macgowania


   

 Hudsonelpidia


  Neoichthyosauria  


 Temnodontosaurus


  Leptonectidae  

 Leptonectes


   

 Excalibosaurus


   

 Eurhinosaurus





   

 Suevoleviathan


   

 Thunnosauria




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Template: Klade / Maintenance / Style

Geographical distribution

At present, Suevoleviathan has only been found in Germany. Without exception, all finds come from the area around Holzmaden and Bad Boll .

Stratigraphy and time horizon

Suevoleviathan occurs from the Lias epsilon II, 4/5 to the Lias epsilon III in the Lower Toarcium of the Lower Jurassic .

Selection of museums with copies

Germany

Sources and References

literature

  • Christopher McGowan, Ryosuke Motani: Ichthyopterygia , Handbook of Paleoherpetology, Part 8, Verlag Dr. Friedrich Pfeil, 2003.

Web links

Commons : Suevoleviathan  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e M. W. Maisch: A new ichthyosaur genus from the Posidonia Shale (Lower Toarcian, Jurassic) of Holzmaden, SW-Germany with comments on the phylogeny of post-Triassic ichthyosaurs. In: Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 209 , 1998, pp. 47–78.
  2. ↑ a b c d e M.W. Maisch: New specimens of the rare ichthyosaur genus Suevoleviathan MAISCH 1998 from the lower Jura of southwest Germany. Geologica et Paleontologica 35 , 2001, pp. 145-160.
  3. ^ MW Maisch, AT Matzke: The Ichthyosauria. In: Stuttgart contributions to natural history series B (geology and palaeontology) 298 , 2000, pp. 1–159.
  4. ↑ R. Motani: Phylogeny of the Ichthyopterygia. In: Journal of Vertebrate Paleontology 19 (3), 1999, pp. 473-496.
  5. ↑ a b c E. A. Buchholtz: Swimming Styles in Jurassic Ichthyosaurs. In: Journal of Vertebrate Paleontology 22 (1), 2001, pp. 61-73.
  6. ^ W. Riegraf, G. Werner, F. Lörcher: Der Posidonienschiefer: Biostratigraphy, fauna and facies of the southwest German sub-arcium (Lias ε). Ferdinand Enke Verlag Stuttgart, 1984, pp. 195ff.
  7. ^ RD Marek, BC Moon, M. Williams, and MJ Benton: The Skull and Endocranium of a Lower Jurassic Ichthyosaur based on Digital Reconstructions. Palaeontology 58 , 2015, pp. 723-742.