Biology:Plutoniosaurus

Short description: Extinct genus of reptiles

Plutoniosaurus Temporal range: Early Cretaceous, 135-130 Ma
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Order:	†Ichthyosauria
Family:	†Ophthalmosauridae
Subfamily:	†Platypterygiinae
Genus:	†Plutoniosaurus Efimov, 1997
Species
†P. bedengensis Efimov, 1997 (Type)

Plutoniosaurus is an extinct genus of ophthalmosaurid ichthyosaur of uncertain validity from the Early Cretaceous (late Hauterivian) of the vicinity of Ulyanovsk, European Russia.

Taxonomy

Plutoniosaurus was named by Vladimir Efimov in 1997 based on the holotype specimen UPM 2/740, a partial skeleton. In 1999, Maxim Arkhangel'skii synonymized the genus with Platypterygius, as did Michael Maisch and Andreas Matzke in 2000. While agreeing with the synonymy, Christopher McGowan and Ryosuke Motani considered P. bedengensis to be a nomen dubium within the genus in 2003, too poorly known to identify as a distinct species. In 2016, Valentin Fischer and colleagues considered the original description was too vague to confidently distinguish the genus and noted that the illustrations did not always match the written description. They thus regarded Plutoniosaurus bedengensis as a species inquirenda, while noting the possibility that it is the same species as the nearly coeval Simbirskiasaurus from the same region.

Phylogeny

Zverkov and Efimov (2019) recovered Plutoniosaurus in a polytomy with the type species of Platypterygius and Leninia. The following cladogram shows a possible phylogenetic position of Plutoniosaurus in Ophthalmosauridae according to the analysis performed by Zverkov and Jacobs (2020).

Ophthalmosauria

Ophthalmosaurinae         Acamptonectes densus       Mollesaurus periallus       Ophthalmosaurus natans     Ophthalmosaurus icenicus                   Gengasaurus nicosiai         Nannopterygius yasykovi       Nannopterygius enthekiodon     Nannopterygius saveljeviensis     Nannopterygius borealis             Arthropterygius volgensis       Arthropterygius lundi     Arthropterygius thalassonotus       Arthropterygius hoybergeti     Arthropterygius chrisorum                   Platypterygiinae     Brachypterygius extremus     Aegirosaurus leptospondylus       Muiscasaurus catheti       Leninia stellans       Sveltonectes insolitus       Athabascasaurus bitumineus       Platypterygius americanus         Acuetzpalin carranzai     Platypterygius sachicarum     Caypullisaurus bonapartei             Grendelius mordax     Grendelius alekseevi     Grendelius pseudoscythicus     Grendelius zhuravlevi             Undorosaurus kielanae       Undorosaurus nessovi     Undorosaurus gorodischensis                 Platypterygius australis       Plutoniosaurus bedengensis     Simbirskiasaurus birjukovi     Platypterygius hercynicus     Sisteronia seeleyi     Platypterygius platydactylus     Maiaspondylus lindoei

See also

• List of ichthyosaurs
• Timeline of ichthyosaur research

References

Wikidata ☰ Q22286449 entry