Name Aegirosaurus
Class Chordata,‭ ‬Reptilia,‭ ‬Ichthyosauria,‭ ‬Ophthalmosauridae,‭ ‬Platypterygiinae
Name Translation Aegir Lizard
Period Tithonian (Jurassic) to Valanginian (Cretaceous)
Location Germany, France
Diet Piscivore/Carnivore
Size 2 meters long

Aegirosaurus is an extinct genus of platypterygiine ophthalmosaurid ichthyosaur known from the late Jurassic and early Cretaceous of Europe. It was originally named as a species of Ichthyosaurus, but has now been proven to be its own genus.

Discovery and species[]

Originally described by Wagner (1853) as a species of the genus Ichthyosaurus (I. leptospondylus), the species Aegirosaurus leptospondylus has had an unstable taxonomic history. It has been referred to the species Ichthyosaurus trigonus posthumus (later reclassified in the dubious genus Macropterygius) in the past, and sometimes identified with Brachypterygius extremus. In 2000, Bardet and Fernández selected a complete skeleton in a private collection as the neotype for the species I. leptospondylus, as the only other described specimen was destroyed in World War II. A second specimen from the Munich collection was referred to the same taxon. Bardet and Fernández concluded that the neotype should be assigned to a new genus, Aegirosaurus. The name means 'Aegir (teutonic god of the ocean) lizard with slender vertebrae'.

Within the Ophthalmosauridae, scientists once believed Aegirosaurus was most closely related to Ophthalmosaurus. However, many recent cladistic analyses found it is more closely related to Sveltonectes (and probably to Undorosaurus). Aegirosaurus' lineage was found to include Brachypterygius and Maiaspondylus, too, and to nest within the Platypterygiinae, which is the sister taxon of Ophthalmosaurinae.

Stratigraphic range[]