Borealosuchus, Brochu, 1997

Borealosuchus and Planocraniidae

Our CW3 and RW3 analyses resolves Borealosuchus as the sister-taxon of Brevirostres, similar to the results presented in Brochu (2001) ( Fig. 6). This is in contrast to Pol et al. (2009), where it is one of the earliest diverging eusuchian lineages ( Holliday & Gardner, 2012) and formed a polytomy with Gavialoidea; and Puértolas et al. (2011), where it was placed as the sister-group to Gavialoidea. Its position as the sister-taxon to Brevirostres in our analyses is based on: alveolar walls raised relative to ventral surface of maxilla (character 131); a weak postorbital bar (its width less than half of the bar height) (character 213); anterior edge of choanae closer to posterior edge of pterygoid flanges than suborbital fenestrae (character 352); and third maxillary alveolus larger in diameter than second alveolus (character 391). Our character scores mostly agree with those in previous studies, but they are overwhelmed by the addition of other characters in our revised dataset.

Planocraniidae sensu Brochu (2013), who defined it as consisting of both species of Planocrania + Boverisuchus , is not identified in any of our analyses. This is despite the fact that our scores include the same apomorphies that grouped the three species together in Brochu (2013): labiolingually compressed teeth on both maxilla and dentary (characters 396 and 414). However, in our analysis, these two characters do not provide a strong enough signal to resolve Planocraniidae. Both CW3 and RW3 analyses place the two Planocrania species as the sister-group of Crocodylidae on the basis of the lateral carotid foramen opening dorsal to the basisphenoid lateral exposure (character 318) and parallel to subparallel lateral edges of the anterior half of the interfenestral bar between the suborbital fenestrae (character 366). Boverisuchus is placed as the sister-taxon of Brevirostres, based on: a single projection of the postorbital bar (character 216); the posteriormost maxillary alveolus being closer to the anterior margin of the orbit than the posterior margin (character 394); and dentary teeth occluding lingually to maxillary teeth (character 425).