A new open access paper
by Ezcurra, Montefeltro and Butler 2016 provides several first time ever color photos of rhynchosaur skulls and a cladogram of rhynchosaur relationships (Fig. 1). It’s a good paper, with good interrelationships. Unfortunately the wrong outgroup, the Protorosauria, was chosen.
the large reptile tree nests rhynchosaurs with trilophosaurs and rhynchocephalians (sphenodontids, Fig. 2), not protorosaurs. Taxon inclusion will help you recover this relationship, too, if you wish to repeat the experiment. Ezcurra et al. (2016) relied on untested tradition, but that tradition brings with it a certain air of credulity as Prolacerta does indeed converge with Mesosuchus in several regards. But parsimony prevails when the following lepidosauromorphs (Fig. 2) are included in analysis. This is a relationship best left to software, not eyeballs and paradigms.
In the transition from rhynchocephalians to rhynchosaurs,
this clade had an interesting radiation that included Leptosaurus, Sapheosaurus, Trilophosaurus and Azendohsaurus (which also nests with protorosaurs when the taxa in figure 2 are excluded, before producing rhynchosaurs. Priosphenodon (Fig. 3), typically considered a Cretaceous rhynchocephalian, is a transitional taxon for some reason left off of the Ezcurra et al. 2016 taxon list that nests closer to rhynchosaurs than Mesosuchus does in the large reptile tree. Probably because all rhynchosaurs died out by the Jurassic.
Ezcurra MD, Montefeltro F and Butler RJ 2016. The Early Evolution of Rhynchosaurs. Frontiers in Ecology and Evolution 3:142 (23 pgs) doi: 10.3389/fevo.2015.00142 http://dx.doi.org/10.3389/fevo.2015.00142