The Early Jurassic ichthyosaur Stenopterygius in the collection of the Museo di Scienze della Terra, Università di Catania (Italy)

The "Bonaventura Gravina" Collection of the Earth Science Museum of Catania (Italy) includes an ichthyosaur specimen of unknown geographic and stratigraphic provenance, age, and taxonomic determination. On comparison with other fossils from the same collection it was established that the specimen is from Böll, southwestern Germany; the ammonites preserved on the same slab indicate an early Toarcian age. Based on the available information it is suggested that it comes from the Early Jurassic Posidonia Shale (Posidonienschiefer), which is known worldwide for its ichthyosaur remains. A morphological comparison with Toarcian ichthyosaurs allowed the fossil remains to be referred to an adult specimen of Stenopterygius, a mid-sized ichthyosaur genus common in the Toarcian of Southern Germany. The phylogenetic analysis by parsimony supports this conclusion.