Duerosuchus is a rather small crocodilian from the Eocene of Spain. When initially described it was placed closely to the clade Brevirostres (Gators and Crocs), but a later phylogenetic analysis found out that it was actually a member of the Planocraniidae.
Planocraniidae is a family of terrestrial crocodilians (or more basal Eusuchians) that lived in Eurasia and America during the Paleocene and Eocene. The family also includes the much larger Boverisuchus magniforns from Germany and Boverisuchus vorax from America, as well as Planocrania from China. Effectively speaking, Boverisuchus is the animal previously known as Pristichampsus, because Pristichampsus was based on fragmentary material that wasn't diagnostic enough. So out with the old, in with the new.
Planocraniids were one of multiple groups of crocodiles inhabiting the Eocene rainforests, adapted to a more running lifestyle with toes tipped by hooves and later ziphodont (compressed and serrated) teeth. At least in Boverisuchus. The teeth of Duerosuchus and Planocrania were already flattened, but not serrated. The other three prominent croc groups in the Eocene jungles of the northern hemisphere were crocodiles, represented by "Asiatosuchus" in Spain, alligatoroids, present with Diplocynodon, and Sebecids, a group thats much more ancient and not part of the crown group of crocodiles. Sebecids are present with Iberosuchus, another terrestrial hunter, but one that was much larger than Duerosuchus. (bottom image by Ortega et al.)
