Osteology of Carnufex 2015, 2016

Drymala and Zanno 2016 returned to their description of Carnufex,
(Fig. 1) a partial disarticulated basal crocodylomorph they published on a year earlier (Zanno, Drymala, Nesbitt and Schneider 2015; Fig. 2).

Figure 2. Data from Drymala and Zanno 2016 below. Elements colorized and moved around here above. It's always better NOT to use freehand illustrations.

Figure 1. Below: Data from Drymala and Zanno 2016. Above: Elements colorized and reconstructed  here. I prefer moving elements around to freehand illustration. The size of the lacrimal changes from the earlier paper (see figure 2).

There is also a strange data problem here. 
The 2015 paper included a reconstruction (Fig. 2) with a smaller lacrimal. The 2016 paper includes data and a reconstruction (Fig. 1) with a larger lacrimal.

Figure 3. Carnufex is basically a giant Pseudhesperosuchus. Here they are compared to one another to scale and with skulls side by side. Dark gray areas are imagined on the original at bottom by Zanno et al. Click to enlarge. With a skull 4x larger than that of Pseudhesperosuchus, Carnufex was a likely 4.4 meter long bipedal killer. Note the smaller orbit and deeper jugal. Both neural arches are missing a centrum.

Figure 2. Carnufex (from 2015 data) compared to Pseudhesperosuchus. Dark gray areas are imagined on the original at bottom by Zanno et al 2015. Compare to 2016 data in figure 1.

Unfortunately
their 2016 cladogram (Fig. 3) omitted several taxa key to understanding Carnufex and the clade Crocodylomorpha in the large reptile tree (LRT, 1697+ taxa; subset Fig. 4). For instance, in the LRT only Dinosauromorpha + Crocodylomorpha combine to form the clade Archosauria. So one wonders why no basal dinosaurs appear in the 2016 cladogram. Worse yet, a large number of basal bipedal crocodylomorphs are absent (list below in red at left).

Figure 1. Carnufex cladogram by Drymala and Zanno 2016. Color overlays added here.

Figure 3. Carnufex cladogram by Drymala and Zanno 2016. Color overlays added here. The phytosaur, Machaeoroprosopus does not belong in this list of euarchosauriformes. Turfanosuchus is a basal poposaur in the LRT. Gracilisuchus is a basal crocodylomorph in the LRT, so I suspect bad scores for those two taxa.

Figure 1. Subset of the LRT focusing on the Crocodylomorpha, dorsal scutes, elongate proximal carpals, bipedality and clades.

Figure 4. Subset of the LRT focusing on the Crocodylomorpha, dorsal scutes, elongate proximal carpals, bipedality and clades.

After all the scoring changes
the prior nesting in the LRT of Carnufex with Pseudhesperosuchus (Fig. 5) remains the same, evidence that sometimes changes are not that important taxonomically.

Figure 5. Skull of Pseudhesperosuchus, a basal bipedal crocodylomorph close to Carnufex.

Figure 5. Skull of Pseudhesperosuchus, a basal bipedal crocodylomorph close to Carnufex.

In the LRT
dinosaurs are the closest outgroup to the basal bipedal crocs. In the LRT Pseudhesperosuchus is the closest taxon to Carnufex. Together these exclusions from the two Carnufex papers are errors of omission that change some hypothetical relationships.

If you’re going to use a comprehensive list of pertinent taxa,
it’s best to figure out first which taxa are the most pertinent. That’s the value of the LRT, where more taxa solve more problems here than more characters and fewer taxa do in smaller studies. You can always delete unrelated taxa once you have the proper phylogenetic context and wish to increase the focus of your study.


References
Drymala SM and Zanno LE 2016. Osteology of Carnufex carolinensis (Archosauria: Psuedosuchia) from the Pekin Formation of North Carolina and Its Implications for Early Crocodylomorph Evolution. PLoS ONE 11(6): e0157528. doi:10.1371/journal.pone.0157528
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.

wiki/Carnufex
wiki/Pseudhesperosuchus

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