Proganochelys

Name: Proganochelys ‭(‬Early shell‭)‬.
Phonetic: Pro-gan-o-kel-iss.
Named By: Georg Baur‭ ‬-‭ ‬1887.
Synonyms: Chelytherium,‭ ‬Psammochelys,‭ ‬Stegochelys,‭ ‬Triassochelys.
Classification: Chordata,‭ ‬Reptilia,‭ ‬Anapsida‭?‬,‭ ‬Testudines.
Species: P.‭ ‬quenstedti‭ (‬type‭)‬,‭ ‬P.‭ ‬ruchae.
Diet: Herbivore.
Size: About‭ ‬1‭ ‬meter long.
Known locations: Germany‭ ‬-‭ ‬Löwenstein Formation‭ & ‬Trossingen Formation,‭ ‬Greenland‭ ‬-‭ ‬Fleming Fjord Formation,‭ ‬and Thailand‭ ‬-‭ ‬Huai Hin Lat Formation.
Time period: Norian to Rhaetian of the Triassic.
Fossil representation: Several individuals.

       For well over a hundred years Proganochelys was regarded as the oldest known turtle,‭ ‬a title the genus held until the‭ ‬2008‭ ‬description of Odontochelys,‭ ‬a slightly earlier genus that lived in the Carnian stage of the Triassic.
       Proganochelys had a developed carapace and plastron,‭ ‬the upper and lower parts of the shell respectively.‭ ‬These were formed by bony plates that had fused to the ribs and in life the plates would have had a covering of horn.‭ ‬Proganochelys was still quite primitive in some respects,‭ ‬one of the key things being that the head could not retract underneath the shell.‭ ‬Therefore to provide additional protection,‭ ‬the neck had a‭ ‬covering of spines that would have made it much more difficult for a predator to close its mouth around the neck.‭ ‬The tail of Proganochelys was quite long for a turtle,‭ ‬and it too had a covering of spines,‭ ‬but more interestingly the tail ended with a small club.
       Fossils of Proganochelys are most often associated with Germany where the genus was first discovered,‭ ‬though at least three specimens of a second species named P.‭ ‬ruchae are known from Thailand.‭ ‬Proganochelys is‭ ‬also one of the few prehistoric animals to be identified as once living in what would become Greenland.

Further reading
- Skull morphology of the oldest turtles: a preliminary description of Proganochelys quenstedti. - Journal of Vertebrate Paleontology. 3 (1): 25–28. - E. S. Gaffney & L. J. Meeker - 1983.
-‭ ‬Proganochelys ruchae n.‭ ‬sp.,‭ ‬chélonien du Trias supérieur de Thaïlande‭ [‬Proganochelys ruchae n.‭ ‬sp.,‭ ‬chelonian from the Upper Triassic of Thailand‭] ‬-‭ ‬F.‭ ‬de Broin‭ ‬-‭ ‬1984.



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