Carnufex: a new Triassic proto-dinosaur (not a proto-croc)

Carnufex carolinensis (NCSM 21558, Zanno et al. 2015, Fig. 1) is a new Carnian (earliest Late Triassic, 231 mya), croc(?) based on fragments of a skull, a cervical neural spine, a dorsal neural spine and a humerus (Fig. 1). And yes, it was a likely biped, but it was a little closer to dinos than to crocs as it nests with the proto-dinos Pseudhesperosuchus and Junggarsuchus.

Unfortunately the Zanno tree did not include Pseudhesperosuchus
in their cladogram and that is the sister taxon to Carnufex in the large reptile tree. Unfortunately Zanno et al. used the very troubled matrix of Butler et al. 2014, derived from the equally troubled matrix of Nesbitt 2011 in which pterosaurs are included derived from parasuchians and sisters to ornithosuchids, aetosaurs and lagerpetonids. As you can tell, almost nothing could be worse and that cladogram has now been through at least four generations of papers. Earlier we looked at problems with papers based on Nesbitt et al. 2011 here and here.

Zanno et al. nest Carnufex between the giant rauisuchians Rauisuchus + Postosuchus and tiny bipedal crocs, reporting that Carnufex bridges the gap between them. Also missing from their tree is Decuriasuchus, which does bridge the gap between basal (not derived) rauisuchians like Vjushkovia (also missing from their tree) and basal poposaurs like Turfanosuchus, which gives rise to Gracilisuchus at the base of the Archosauria (dinos and birds + crocs).

In the Zanno et al. tree Turfanosuchus is derived from a sister to the armored Revueltosaurus and the odd Ornithosuchus, in turn the sister of tiny flying pterosaurs in that tree. I’ll stop there before it gets weirder.

Without Pseudhesperosuchus
the reconstruction of Carnufex goes a little bit astray (Fig. 1). Even so, you can readily see that that humerus is so small compared to the skull that Carnufex was a likely biped (to their credit Zanno et al. recognized this despite lacking hind limb material) just like Pseudhesperosuchus. 

Unfortunately the Zanno et al. tree did not nest
basal crocs  just a short phylogenetic step from basal dinos. Thus, with taxon exclusion they did not recognize that Carnufex is closer to basal dinos than to basal crocs and not related to derived rauisuchians. Hopefully someone out there will recognize this phylogenetic solution someday.

The origin of crocs + dinos still sits with Gracilisuchus. Taxon exclusion and inaccurate matrix scoring are keeping the pros away from replicating this very robust result.

References
Butler RJ. et al. 2014. New clade of enigmatic early archosaurs yields insights into early pseudosuchian phylogeny and the biogeography of the archosaur radiation. BMC Evol. Biol. 14, 128.
Nesbitt SJ 2011. The early evolution of archosaurs: relationship and the origin ofmajor clades. Bull. Amer. Mus. Nat. Hist. 352, 1–292.
Zanno LE, Drymala S, Nesbitt SJ and Schneider VP 2015. Early Crocodylomorph increases top tier predator diversity during rise of dinosaurs. Scientific Reports 5:9276 DOI: 10.1038/srep09276.