Grendelius


Grendelius is a genus of platypterygiinae ophthalmosaurid ichthyosaur from the Late Jurassic of the UK and European Russia.

Taxonomy

The type species, Grendelius mordax, was described in 1976 on the basis of CAMSM J.68516, a complete skull with associated postcranial elements from the Kimmeridge Clay of England. Later, it was reassigned to Brachypterygius because differences between the two species were considered insufficient to warrant separate genera, or even species.
Efimov, 1998 named a new genus of ichthyosaur, Otschevia pseudoscythica on the basis of a single specimen from the Pseudoscythia Zone of Ulyanovsk, Volga region, Russia. Later, Arkangelsky, 1998 described Brachypterygius zhuravlevi from a Tithonian-stage locality in Saratov, Russia, subsequently referring it to Otschevia zhuravlevi. Maisch & Matzke, 2000 considered both Russian taxa to be synonyms of each other, and referred the new combination B. pseudoscythica to Brachypterygius, although they misspelt this as B. pseudoscythius. Thus, Grendelius and Otschevia are considered to be junior synonyms of Brachypterygius. Arkhangelsky named Otschevia alekseevi in 2001, also from the Late Jurassic of Russia. While McGowan and Motani considered these Russian taxa to be junior synonyms of B. extremus, Maisch retained them, and B. mordax, as separate species. A new paper published in 2015 found Grendelius and Otschevia generically distinct from the Brachypterygius type species and more derived within Platypterygiinae, being more closely related to Platypterygius than to Brachypterygius.