Largest Carnivourous Dinosaur Ever Found in Europe

[DinoFan83]

Other post deleted as it's no longer relevant. It looks like we have an even larger megalosaurid specimen (as in >8 tonnes) that may or may not uphold the thread.

Rauhut et al. 2018 has described an anterior caudal centrum of a very large Iberian megalosaurid catalogued as MUJA-1913. They suggest it's the largest carnivorous dinosaur found so far from Europe, and I think they are very likely correct. Relevant quotes from the paper are as follows.

Quote:One striking feature of the vertebra from the Vega Formation is its enormous size. With a posterior centrum height of 150 mm, MUJA-1913 is larger than most anterior caudals for which measurements can be found in the literature. In particular, anterior caudals of Torvosaurus tanneri are about 25% smaller (Britt, 1991), an anterior caudal of Spinosaurus aegyptiacus is c. 10% smaller (Stromer, 1915), and one of the largest theropod caudals from the Jurassic, for which measurements were given, a possible carcharodontosaurid caudal from the Tendaguru Formation (Rauhut, 2011), is also c. 25% smaller than the specimen described here. Larger caudal vertebrae are present in the gigantic Cretaceous carcharodontosaurids (Canale, Novas & Pol, 2015) and Tyrannosaurus (Brochu, 2003), but might also be found in the largest allosauroid predators of the Late Jurassic Morrison Formation of the western USA (Chure, 1995 , 2000 ; Williamson & Chure, 1996), though no measurements are available in the literature for these specimens. However this may be, Hendrickx & Mateus (2014) argued that the holotype of Torvosaurus gurneyi represented the largest theropod dinosaur yet recorded from Europe (see also specimens described by Malafaia et al., 2017a). This specimen includes a partial anterior caudal vertebra, the posterior articular surface of which is about 15% smaller than that of MUJA-1913. Thus, given that the specimen from the Vega Formation probably belongs to a closely related taxon, this specimen probably represents the largest theropod dinosaur recorded so far in Europe, and represents an apex predator of more than 10 m in length.

Note that while a comparison to the anterior caudal vertebra of T. gurneyi is made, this comparison is not of much use as that caudal was found isolated and it is unknown what size Torvosaurus it belongs to. I therefore consider another relatively large and complete megalosaurid (Megalosaurus) to be a superior option for estimating the size of this specimen, and it is what will be used here.

For the Megalosaurus base: Our largest postcranial specimens can be estimated between 8 (Paleonerd01) and 9 (Thomas Holtz) meters long, depending on the tail length, and here I will be assuming the mean of that. They are also about 2 tonnes in mass, as was explained here. 

Some things should be noted, however:

-For this post, instead of my hyperlinked cross-scaled version, I will be using the original Megalosaurus skeletal by GetAwayTrike. This is because while the relative head and arm size in that skeletal are almost certainly too small for Megalosaurus itself, they are likely to be close to the mark for this megalosaurid because using my cross scaled version here results in an animal with an almost 2.3 meter long skull (significantly less parsimonious than the 185.3 cm estimate the original yields) as well as very large arms, which an >8 tonne megalosaurid would benefit significantly less from than a 2 tonne megalosaurid would.
TLDR: I expect this megalosaurid to be closer to GetAwayTrike's original skeletal in terms of arm and head size than to my cross scaling for Megalosaurus given the size disparity.

Onto its size: The largest anterior caudal in the hyperlinked Megalosaurus has a centrum 9.3 cm tall given the scalebar, substantially smaller than the 15 cm tall caudal centrum of MUJA-1913. Given everything above, this leads to a 13.7 meter long and 8.36 tonne animal with a robustly built 185.3 cm skull. Assuming this is roughly accurate, I consider this animal a much better choice for Europe's largest known carnivorous dinosaur than the Torvosaurus gurneyi holotype, and it would be among the largest known theropods of all, being very similar in size to more famous specimens like the 8.17 tonne Giganotosaurus holotype or the 7.9 tonne Sue. 

However, this does not mean that T. gurneyi itself isn't the largest known carnivorous dinosaur from Europe given known material. That may very well be the case.

Quote:Christophe Hendrickx wrote:

In this paragraph, Rauhut and colleagues wrote the following text:

Quote:"[...] Hendrickx & Mateus (2014) argued that the holotype of Torvosaurus guerneyi represented the largest theropod dinosaur yet recorded from Europe (see also specimens described by Malafaia et al., 2017a). This specimen includes a partial anterior caudal vertebra, the posterior articular surface of which is about 15% smaller than that of MUJA-1913. Thus, given that the specimen from the Vega Formation probably belongs to a closely related taxon, this specimen probably represents the largest theropod dinosaur recorded so far in Europe, and represents an apex predator of more than 10 m in length."

Given MUJA-1913's morphology, megalosaurid affinity, size and paleogeographic and stratigraphic distributions, I am sure that the authors would agree that this specimen could likely belong to Torvosaurus gurneyi itself and not automatically a closely related taxon.

Kind regards,

Christophe Hendrickx

Quote:Oliver Rauhut wrote:

Hi Christophe, Indeed, as we said on page 14: "Given that the genus Torvosaurus has been identified from the Late Jurassic of the Iberian Peninsula (Antunes & Mateus, 2003; Hendrickx & Mateus, 2014; Malafaia et al., 2017a), this vertebra might represent this taxon, but a positive generic or specific identification of this incomplete element is impossible." Thus, this moght very well be Torvosaurus gurneyi or another species of the genus Torvosaurus, but the material is still insufficient...

Hope this helps to clarify for all. Reply