Bennett Moves Pterosaurs to the Base of the Archosauriformes

Earlier we looked at Bennett (2012) in which he shifted pterosaurs back to the more primitive lumbering and aquatic archosauriforms Proterosuchus and Erythrosuchus (Fig. 1). That moved the former nesting away from dinosaursScleromochlus, Proterochampsids and Parasuchians, the previous archosaur ‘favorite candidates,’ which we earlier considered “strange bedfellows.”

It’s worth reiterating
With the same title and publisher, Bennett (2013) reports from his abridged abstract: “A previous analysis of the phylogenetic position of the Pterosauria argued that pterosaurs were not closely related to dinosaurs as is generally accepted, but rather were outside the crown group Archosauria. However, that study was dismissed for the use of inappropriate methods. Here, the data set from that analysis was divided into five partitions: […] Lastly, the data set was updated with additional characters and taxa from recent analyses, tested as before, and when analysed, suggested that the Pterosauria were basal archosauriforms well outside the crown group Archosauria (Fig. 1).

Figure 1. From Bennett 2012 in which he mixes lepidosaurormorpha (in blue) with euarchosauriformes  (in yellow) and pararchosauriforms (in pink). Nearly every sister in this "stone soup" is a strange bedfellow if you think about it.

Figure 1. From Bennett 2012 in which he mixes lepidosaurormorpha (in blue) with euarchosauriformes (in yellow) and pararchosauriforms (in pink). Nearly every sister in this “stone soup” is a strange bedfellow if you think about it. Anurognathus and kin are basal pterosaurs, though Anurognathus is Late Jurassic, so there are other problems here too, other than the use of suprageneric taxa.

Earlier I noted that when pterosaurs are stripped of their closest kin among the Tritosauria / Fenestrasauria down to and including Huehuecuetzpalli, they do indeed nest with Proterosuchus. 

That is what Bennett (2012, 2013) did,
then further examined the various partitions (one with characters associated with cursorial digitigrade bipedal locomotion, and the other four with characters from the skull and mandible, postcranial axial skeleton, forelimb, and hindlimb), for incongruence. This doesn’t help one bit when you ignore the only series of taxa with a gradual accumulation of pterosaurian traits, the tritosaur fenestrasaurs.

Bennett’s use of suprageneric taxa is also a problem.

And really, Proterosuchus??
Is that the best candidate the opposite team can muster?? I think this is yet one more case of experts casting a blind eye toward the subject of pterosaur origins.

References
Bennett SC 2012. The phylogenetic position of the Pterosauria within the Archosauromorpha re-examined. Historical Biology. iFirst article, 2012, 1–19.
Bennett SC 2013. The phylogenetic position of the Pterosauria within the Archosauromorpha re-examined. Historical Biology 25(5-6): 545-563.

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