Platypterygius

Platypterygius
Temporal range: Early - Late Cretaceous
P. americanus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Ichthyosauria
Family: Ophthalmosauridae
Subfamily: Platypterygiinae
Genus: Platypterygius
von Huene, 1922
Species
  • P. platypterygius (Broilli, 1907) type
  • P. americanus (Nace 1939) McGowan 1972
  • P. hercynicus Kuhn, 1946
  • P. kiprijanoffi (Romer 1968) McGowan 1972?
  • P. australis (McCoy, 1867)
  • P. ochevi Arkhangel’sky et al., 2008 [1]
  • P. sachicarum Páramo, 1997

Platypterygius ('Flat wing (flipper)', von Huene 1922) is an ichthyosaur of the family Ophthalmosauridae. It is most closely related to the genera Caypullisaurus and Brachypterygius.[2]

Discovery and species

Skull of P. sachicarum in the Paleontological Museum in Villa de Leyva, Colombia

Fossils are known from Australia, Russia, United States of America, Colombia,[3] Western Europe and possibly New Zealand. There are seven named species. Both adults and juveniles have been unearthed, including newborns and pregnant females. Like other ichthyosaurs, Platypterygius gave live birth.

The remains from Australia were originally called Ichthyosaurus australis. They are from the Toolebuc Formation and Allaru Mudstone (Albian, Lower Cretaceous) of Flinders River and other localities in north central Queensland. In 1990 Wade erected the species name P. longmani to include all remains previously referred to I.australis .

The cladogram below follows the topology from a 2010 analysis by Patrick S. Druckenmiller and Erin E. Maxwell.[4]

Thunnosauria 

Ichthyosaurus




Stenopterygius




"Ophthalmosaurus" natans


 Ophthalmosauridae 


Aegirosaurus



Ophthalmosaurus (type species)





Mollesaurus




Athabascasaurus




Brachypterygius




Arthropterygius



Caypullisaurus



"Platypterygius" hercynicus



"Platypterygius" australis (=Longirostria)[5]



Platypterygius (type species)




Maiaspondylus



"Platypterygius" americanus (=Tenuirostria)[5]











Palaeobiology

P. kiprijanovi - Albian-Cenomanian of Kursk region (Russia)

Platypterygius reached a length of about 7 m (23 ft). It had a long snout and a powerful finned tail. There are more digits in the front flippers than is usual in ichthyosaurs; they are tightly bound in rows, giving a broad, flat appearance . This unusual characteristic gives the genus its name, meaning 'flat wing.' Furthermore, some of the wrist bones have disappeared entirely. CAT scans on a juvenile specimen strongly suggest that Platypterygius was deaf.

Species

Formerly referred species

References

  1. Arkhangel’sky, M. S., Averianov, A. O., Pervushov, E. M., Ratnikov, V. Yu, and Zozyrev, N. Yu., 2008, On ichthyosaur remains from the Cretaceous of the Voronezh region: Paleontological Journal, v. 42, n. 3, p. 287-291.
  2. Fernández M. 2007. Redescription and phylogenetic position of Caypullisaurus (Ichthyosauria: Ophthalmosauridae). Journal of Paleontology 81 (2): 368-375.
  3. Páramo, M. E. Platypterygius sachicarum (Reptilia, Ichthyosauria) nueva especie del Cretácico de Colombia. Revista Ingeominas 6, 1997: 1–12
  4. Patrick S. Druckenmiller and Erin E. Maxwell (2010). "A new Lower Cretaceous (lower Albian) ichthyosaur genus from the Clearwater Formation, Alberta, Canada". Canadian Journal of Earth Sciences 47 (8): 1037–1053. Bibcode:2010CaJES..47.1037D. doi:10.1139/E10-028.
  5. 5.0 5.1 Arkhangel’sky, M. S., 1998, On the Ichthyosaurian Genus Platypterygius: Palaeontological Journal, v. 32, n. 6, p. 611-615.
  6. 6.0 6.1 Valentin Fischer, Maxim S. Arkhangelsky, Darren Naish, Ilya M. Stenshin, Gleb N. Uspensky and Pascal Godefroit (2014) Simbirskiasaurus and Pervushovisaurus reassessed: implications for the taxonomy and cranial osteology of Cretaceous platypterygiine ichthyosaurs. Zoological Journal of the Linnean Society 171(4): 822–841 DOI: 10.1111/zoj.12158 http://onlinelibrary.wiley.com/doi/10.1111/zoj.12158/abstract

External links