Mystriosaurus
| Mystriosaurus | ||||||||
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Skull of Mystriosaurus laurillardi (formerly holotype of Steneosaurus brevior ) |
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| Temporal occurrence | ||||||||
| Lower Jurassic (lower Toarcian ) | ||||||||
| 182.7 million years | ||||||||
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| Scientific name | ||||||||
| Mystriosaurus | ||||||||
| Kaup , 1834 | ||||||||
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Mystriosaurus is an extinct genus of marine crocodiles from the Teleosauroidea group . First described in the late 18th century , the fossils of the genus look back on a long history of research. While Mystriosaurus has been a synonym for Steneosaurus for the past few decades, recent studies have shown that Mystriosaurus is actually an independent genus. Fossils come from the Lower Jurassic of Germany and the United Kingdom . The currently only known species is Mystriosaurus laurillardi .
description
In comparison to other Thalattosuchia, Mystriosaurus had a medium-long (mesorostrine) snout, which was shorter than that of the Steneosaurus bollensis and Platysuchus living at the same time . The genus differs from other Teleosauroidea, among other things, in the clear ornamentation of the skull bones, the shape of the upper temporal windows and the forward nostril . Mystriosaurus reached a length of about four meters.
Research history
The first skull of the later Mystriosaurus was found in 1776 by Johann Friedrich Bauder , a naturalist and then mayor of the Bavarian town of Altdorf near Nuremberg , in the layers of the local "Altdorf marble" ( Posidonia schist formation ) and aroused the interest of other scientists early on. The geologist Johann Ernst Immanuel Walch first identified the skull as a crocodile in 1776 , while the theologian and paleontologist Johann Samuel Schröter interpreted it as an "ant eater". At around the same time, Johann Wolfgang von Goethe learned of the find and reported it to his friend, the naturalist Johann Heinrich Merck . Merck acquired Bauder's skull and compared it to a gavial . After Merck's death, he came under the then Landgrave Ludwig X in the Naturialienkabinett of Darmstadt . The paleontologist Johann Jakob Kaup , who was based in Darmstadt at the time, finally named the skull as a new species, Mystriosaurus laurillardi .
While Mystriosaurus was recognized as a valid genus in other works of the 19th and 20th centuries, the paleontologist Frank Westphal found in his monograph from 1962 the differences between Mystriosaurus and other teleosauroids of the same time as too small and called Mystriosaurus as a synonym of Steneosaurus bollensis . This view persisted for the next few decades until a team led by Sven Sachs rewrote Bauder's Fund in 2019 and highlighted the differences to other Teleosauroidea. Sachs et al. also assign the Steneosaurus brevior found in the same age layers of British Whitby as a synonym Mystriosaurus laurillardi .
Systematics
Mystriosaurus laurillardi was an early marine crocodile ( Thalattosuchia ) from the teleosauroid superfamily . Within this, the species forms a common clade with other forms such as Teleosaurus , Platysuchus and Mycterosuchus , while Steneosaurus bollensis, originally traded as a senior synonym , is only a distant relative of Mystriosaurus in recent analyzes . A phylogenetic analysis by Sachs et al . (2019) was able to show that Mystriosaurus was apparently more closely related to some Teleosauroidea from China than to other species of the same age from Europe.
Abbreviated cladogram of the Teleosauroidea according to Johnson et al . (2019):
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Trivia
The paleontologist and mineralogist Friedrich August Quenstedt lamented the " barbaric " name Mystriosaurus laurillardi in his work published in 1852. Although it was found by "our fathers", it now bears the name of a French .
literature
Sachs, S., Johnson, MM, Young, MT, & Abel, P. (2019). The mystery of Mystriosaurus : Redescribing the poorly known Early Jurassic teleosauroid thalattosuchians Mystriosaurus laurillardi and Steneosaurus brevior . Acta Palaeontologica Polonica , 64 (3), 565-579. doi: 10.4202 / app.00557.2018
Individual evidence
- ^ Sachs Vertebrate Palaeontology Research, the Mystery of Mystriosaurus . [1]
- ^ Johnson, MM, Young, MT, & Brusatte, SL (2019). Re-description of two contemporaneous mesorostrine teleosauroids (Crocodylomorpha: Thalattosuchia) from the Bathonian of England and insights into the early evolution of Machimosaurini. Zoological Journal of the Linnean Society . doi: 10.1093 / zoolinnean / zlz037
- ↑ Quenstedt, FA (1852). Handbook of Petrefacts , Verlag der H. Laupp'schen Buchhandlung, Tübingen, p. 99.