Placochelys
{{Short description|Extinct genus of reptiles}}
{{Automatic taxobox
| fossil_range = Late Triassic (Norian to Rhaetian),
{{fossil range|221.5|205.6}}
| image = Placochelys.jpg
| image_caption = Restored Placochelys placodonta skull at the Museum für Naturkunde, Berlin
| taxon = Placochelys
| authority = Jaekel, 1902
}}
Placochelys (from {{langx|el|plax, plakos}}, "plate" and {{langx|el|chelys}}, "tortoise"){{cite book |last1=Colbert |first1=Edwin H. (Edwin Harris) |last2=Knight |first2=Charles Robert |title=The dinosaur book: the ruling reptiles and their relatives |date=1951 |publisher=McGraw-Hill |location=New York |page=153 |url=https://archive.org/details/bookruli00colb/page/152/mode/2up}} is an extinct genus of placodont reptiles erected by Otto Jaekel in 1902.
Fossil records
Fossils of Placochelys dates back to the Triassic period (age range: 221.5 to 205.6 million years ago). They have been found in Germany, Austria, Hungary and Italy.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=36537 Paleobiology Database]
Species
This genus includes only one species:
- Placochelys placodonta Jaekel, 1902 (from Upper Ladinian of Hungary)
Description
Placochelys looked remarkably similar to a sea turtle, and grew to about {{convert|90|cm|ft}} in length. It had a flat turtle-like carapace covered with knobbly plates, and a compact triangular skull. Its beaked skull had powerful muscles. It had only two pairs of palatal teeth, a large posterior pair, and a small rostral pair. The specialized broad teeth on the palate, were most likely used for crushing shellfish and hard-shelled prey. Its limbs were paddle-shaped for swimming, although, unlike modern sea turtles, they still had discernable toes, and it also had a short tail.{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|location=London|page= 71|isbn= 1-84028-152-9}}
Gallery
File:Placochelys BW.jpg|Life restoration of Placochelys
File:Placochelyidae - Placochelys placodonta.JPG|Placochelys placodonta fossil skull, lateral view
File:Placochelys placodonta.JPG|Placochelys placodonta skull seen from below
File:Placochelys tooth adnet.jpg|Placochelys tooth from Adnet, Austria
Bibliography
- Jaekel O. 1902. Über Placochelys n. g. und ihre Beeutung fur die Stammesgeschichte der Schildkroten: Neues Jahrbuch für Mineralogie, Geologie und Palaontologie, Abhandlungen, 1902: 127–144.
- Mazin, J.-M. and Pinna, G. 1993. Palaeoecology of the armoured placodonts. Paleontologia Lombarda, N. S. 2: 83–91.
- Rieppel O. and Zanon R.T. 1997. The interrelationships of Placodontia. Historical Biology: Vol. 12, pp. 211–227
- Yin G., in Yin, G., Zhou, X., Cao, Z., Yu, Y, and Luo, Y., 2000, A preliminary study on the Early Late Triassic marine reptiles from Guanling Guizhou, China.
- Rieppel O. 2001. The Cranial Anatomy of Placochelys placodonta Jaekel, 1902, And a Review of the Cyamodontoidea (reptilia, Placodonta) Fieldiana: Geology, New Series, No. 45:1-101.
- Rieppel, O., 2002, The dermal armor of the cyamodontoid placodonts (Reptilia, Sauropterygia): morphology and systematic value: Fieldiana; Geology, new series, n. 46, p. 1-41pp.
References
{{Reflist}}
External links
- [https://archive.org/details/cranialanatomyof45riep The cranial anatomy of Placochelys placodonta Jaekel, 1902, and a review of the Cyamodontoidea (Reptilia, Placodonta) (2001)]
- [http://www.oceansofkansas.com/placodnt.html PLACODONTS: THE BIZARRE ‘WALRUS-TURTLES’ OF THE TRIASSIC]
{{Portal|Paleontology}}
{{Sauropterygia|P.}}
{{Taxonbar|from=Q899251}}
Category:Middle Triassic reptiles of Europe