Cricosaurus bambergensis, a marine crocodile from the Late Jurassic of Germany

In 2017, a team around Sven Sachs from the Naturkunde-Museum Bielefeld studied the find from Wattendorf. It became clear that the specimen represents a species of Cricosaurus, a marine crocodyliform of the family Metriorhynchidae that was previously known from other localities in southern Germany, but that had also been found in Mexico and Argentina (Frey et al., 2002; Young & Andrade, 2009; Herrera et al., 2013). Our detailed investigation revealed that the Bamberg specimen shows anatomical features which were not yet described from any other fossil marine crocodile. This included a peculiar structure of the palate where two depressions are formed which are separated by a keel. What these depressions were good for is not yet known to us. The tail of the new Cricosaurus also revealed some unique characters. The study of the Wattendorf specimen by Sachs, Young, Abel & Mallison was published on April 4th, 2019 in the journal Acta Palaeontologica Polonica (Sachs et al., 2019).

The tail has a mosaic of characters seen in other metriorhynchids. In Metriorhynchoidea there are numerous osteological adaptations to a pelagic lifestyle, one of the most noticeable is the hypocercal tail. The first evidence for a tail bend is known from the late Toarcian, with Magyarosuchus fitosi, a form with a tail bend and full set of osteoderms (Ösi et al., 2018). However, in Metriorhynchidae itself all known forms have a well-developed hypocercal tail and lack osteoderms (Fraas, 1902; Andrews, 1913; Young et al., 2010). Cricosaurus bambergensis is interesting, as it fills a morphological gap between basal metriorhynchids (such as Metriorhynchus superciliosus) and species with longer and sharper tail bends (such as Cricosaurus suevicus, see below).