A leatherback turtle (Testudines, Dermochelyidae) from the Miocene of the Westerschelde, the Netherlands
Peters, M.; Reumer, J.; Bosselaers, M.; Post, K. (2018). A leatherback turtle (Testudines, Dermochelyidae) from the Miocene of the Westerschelde, the Netherlands, in: Farke, A. et al. Society of vertebrate paleontology, october 2018, abstracts of papers 78th annual meeting. pp. 197
In: Farke, A. et al. (2018). Society of vertebrate paleontology, october 2018, abstracts of papers 78th annual meeting. Society of Vertebrate Paleontology: [s.l.]. 255 pp., more
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Document type: Summary
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| Authors | | Top |
- Peters, M.
- Reumer, J.
- Bosselaers, M., more
- Post, K., more
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| Abstract |
The Westerschelde Estuary in The Netherlands is known for its rich vertebrate fossil content. In a recent trawling campaign aimed at sampling a late Miocene marine vertebrate assemblage, over 5000 specimens were retrieved, all currently stored in the Natuurhistorisch Museum Rotterdam. One specimen is a well preserved fragment of a dermochelyid sea-turtle carapace. The Westerschelde specimen is an addition to the scant hypodigm of dermochelyids from the Miocene North Sea. The carapace fragment is described and identified as Psephophorus polygonus. The various secondary marks present on the fragment are suggestive of both predatory and scavenging origin. Based on the assumption that P. polygonus had a similar carapace structure as recent D. coriacea, the minimal size of the complete carapace is estimated to have been 168 x 126 cm. Furthermore, based on the physical traits of the Westerschelde specimen and a reexamination of P. polygonus specimens, including the neotype stored at the Naturhistorisches Museum Wien (Austria), it is argued that previously assigned characteristics cannot be used as discriminative taxonomic properties of dermochelyids in general, and of P. polygonus in particular. An improved cladistic analysis on dermochelyids is performed based on previously defined and new taxonomic characters. Using this analysis it is argued that Psephophorus calvertensis is a junior synonym of P. polygonus. Hence, a new diagnosis of Psephophorus polygonus is defined. The ‘addition’ of P. calvertensis to the species P. polygonus confirms its presence on both sides of the Atlantic Ocean. Therefore, we suggest P. polygonus to have had a cosmopolitan distribution, similar to the extant species Dermochelys coriacea. |
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