Taxa missing from the ancestry of Tyrannosaurus in Lü et al. 2014

Lü et al. 2014
introduced the tyrannosaur, Qianzhousaurus (not yet in the LRT) and their own cladogram of Tyrannosauroidea (Fig. 1). The large reptile tree (LRT, 1406 taxa, subset Fig. 4) and a quick look on Google confirm only the taxa closest to Tyrannosaurus  and Compsognathus (yellow) in common with the Lü et al. taxon list. Taxa in blue are more closely related to Allosaurus in the LRT. Gray taxa are largely incomplete.

Figure 1. Qianzhousaurus cladogram from Lü et al. Colors added based on the LRT.

Figure 1. Qianzhousaurus cladogram from Lü et al. 2014. Colors added based on the LRT. Too little known taxa are scraps.

Look for that dorsally expanded quadratojugal
like the one shown here (Fig. 2, 7) for feathery Zhenyuanlong. Only tyrannosaurs have that. (I just pulled another Larry Martin!) Better yet, you can add the missing taxa from figure 4 to your tyrannosaur/theropod cladogram and see where they nest. Let me know if you confirm or refute the LRT hypothesis of relationships.

Another trait tyrannosaurs share is an upturned premaxilla
(Fig. 7) after Compsognathus. 

Figure 0. Taxa ancestral to tyrannosaurs beginning with the CNJ7 specimen of Compsognathus.

Figure 2. Taxa ancestral to tyrannosaurs beginning with the CNJ7 specimen of Compsognathus. Tianyuraptor has been more recently repaired with an upturned premaxilla based on phylogenetic bracketing and a better fit with bones (Fig. 3).

Short note today. 
We looked at this problem earlier here and here when reviewing the tyrannosaur books that came out a few years ago.

Figure 2. Tianyuraptor skull in situ and reconstructed.

Figure 3. Tianyuraptor skull in situ and reconstructed.

Figure 1. Subset of the LRT focusing on basal theropods. Pink area are more or less goose-sized and smaller taxa.

Figure 4. Subset of the LRT focusing on basal theropods. Pink area are more or less goose-sized and smaller taxa.

Figure 1. Masiakasaurus drawings from Carrano, Loewen and Sertic 2011) with photos from same.

Figure 5. Masiakasaurus drawings from Carrano, Loewen and Sertic 2011) with photos from same. Given these few bones, the LRT nests this taxon as a  tyrannosaur ancestor. close to Tianyruaptor (Fig. 3).

Figure 1. Fukvenator parts to scale lifted from Azuma et al. 2016. Note, the larger skull, hind limb and foot match Zhenyuanlong in size and general morphology. Only the manus is relatively larger. I suspect the smaller skull scale bar.

Figure 6. Fukvenator parts to scale lifted from Azuma et al. 2016. Note, the larger skull, hind limb and foot match Zhenyuanlong in size and general morphology. Only the manus is relatively larger. I suspect the smaller skull scale bar.

The purported long snout of Qianzhousaurus
is little different from that of Alioramus (Fig. 7).

Figure 1. The following taxa nest in the clade of Tyrannosaurus at present: Gorgosaurus, Alioramus, Zhenyuanlong, Huaxiagnathus, Tinayuraptor and Ornitholestes.

Figure 7. The following taxa nest in the clade of Tyrannosaurus at present: Gorgosaurus, Alioramus, Zhenyuanlong, Huaxiagnathus, Tinayuraptor and Ornitholestes.

References
Lü J-C, Yi L-P, Brusatte SL, Yang L, Li H and Chen L 2014. A new clade of Asian Late Cretaceous long-snouted tyrannosaurids. Nature Communications 5:3788. DOI: 10.1038/ncomms4788

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