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Veterupristisaurus, theropod from Tanzania



From: Ben Creisler
bscreisler@yahoo.com
 
 The ref for Veterupristisaurus [without the name mentioned] has first posted 
in November:
http://dml.cmnh.org/2011Nov/msg00495.html
 
This new theropod has not been posted yet by name with an abstract. It's my 
understanding that the volume will be officially published in March 2012. 
Amazon says the official publication date is March 6, 2012: 
http://www.amazon.com/Special-Papers-Palaeontology-Studies-Tetrapods/dp/1444361899
 
However, some places are citing Veterupristisaurus as published in November 
2011:
http://www.bookdepository.com/Special-Papers-Palaeontology-Studies-on-Fossil-Tetrapods-No-86-Barrett/9781444361896
 
 
I'm not sure which year is correct.
Rauhut, Oliver (2011 [2012])
Theropod dinosaurs from the Late Jurassic of Tendaguru (Tanzania). 
Special Papers in Palaeontology: Studies on Fossil Tetrapods 86: 195-239 
doi:10.1111/j.1475-4983.2011. 01084.x.
 
Abstract: 
 
The Tendaguru Formation of south-eastern Tanzania has yielded the only diverse 
theropod fauna known from the Late Jurassic of Gondwana. Theropod remains have 
been recovered mainly from two members of the formation, the Middle and Upper 
Dinosaur members, which span from the Kimmeridgian to the latest Tithonian or 
earliest Cretaceous. Here, four of the described taxa and additional isolated 
remains from this formation are reviewed and evaluated. Labrosaurus(?) stechowi 
Janensch, and Megalosaurus(?) ingens Janensch, are based on isolated teeth that 
do not show any unique derived characters, so these taxa are regarded as nomina 
dubia. Nevertheless, the teeth show character combinations indicative of 
ceratosaurid and carcharodontosaurid relationships, respectively. Ceratosaurus? 
roechlingi Janensch was based on associated fragmentary remains, which probably 
represent more than a single taxon. None of the type material shows diagnostic 
characters, so the
 species is a nomen dubium, and a middle caudal vertebra with possibly 
ceratosaurid affinities is designated as the lectotype. Allosaurus(?) 
tendgurensis Janensch is based on an isolated, poorly preserved basal tetanuran 
tibia, which cannot be diagnosed, so the species is also a nomen dubium. A new 
taxon, Veterupristisaurus milneri gen. et sp. nov., is based on diagnostic 
caudal vertebrae from the Middle Dinosaur Member. These elements show 
carcharodontosaurid synapomorphies and, within this Bade, share a unique 
derived character with the genus Acrocanthosaurus. In total, theropod material 
from the Tendaguru Formation indicates the presence of at least seven different 
species of theropods, including the ceratosaurian Elaphrosaurus bambergi 
Janensch, a probable ceratosaurid, a small abelisauroid, a probable 
abelisaurid, a small, noncoelurosaurian tetanuran, a possible megalosauroid and 
a carcharodontosaurid. Theropod faunas from the Middle and Upper
 Dinosaur members might differ slightly, but are similar in general taxonomic 
composition. In broad systematic terms, the theropod fauna from Tendaguru shows 
greater similarities to Cretaceous Gondwanan theropod faunas than with 
contemporaneous fauna from the North American Morrison Formation, indicating 
that the complex evolutionary and biogeographical history of Cretaceous 
Gondwanan theropod faunas can only be understood in the light of their Jurassic 
origins. 
Allosaurus? tendagurensis  Janensch 1925 Nomen dubium P. 209 
Ceratosaurus? roechlingi  Janensch 1925 Nomen dubium P. 199 
Ceratosaurus? stechowi  (Janensch 1920) Nomen dubium P. 202 
Megalosaurus? ingens  Janensch 1920 Nomen dubium P. 220
=====
Another paper in the same volume that was mentioned earlier without an abstract:
 
Rayfield, Emily J. (2011 [2012])
Structural performance of tetanuran theropod skulls, with emphasis on the 
Megalosauridae, Spinosauridae and Carcharodontosauridae.
Special Papers in Palaeontology: Studies on Fossil Tetrapods 86: 241-253 
10.1111/j.1475-4983.2011.01081.x
 
 
Abstract: 
 
How theropod dinosaur skulls experience stress and strain during the 
application of adductor muscle loads provides a unique insight into their 
feeding behaviour and principles of skeletal construction and scaling. Of 
particular interest are unusual cranial morphologies, such as those seen in the 
spinosaurid theropods, Baryonyx walkeri, Suchomimus tenerensis, Irritator 
challengeri and Spinosaurus aegyptiacus. This study uses the engineering 
technique finite element analysis to reconstruct feeding-related stress and 
strain in the skulls of seven theropod dinosaurs: five non-neotetanurans 
(Afrovenator, Dubreuillosaurus, Monolophosaurus, Spinosaurus and Suchomimus) 
and two basal neotetanurans (Acrocanthosaurus and Carcharodontosaurus). 
Two-dimensional finite element models are created, and simulated adductor 
muscle loads are applied in proportion to the lateral surface area of the 
skull, thereby removing the influence of size and testing the effic
 shape at resisting relative loads. Results show a significant size-related 
trend, with large taxa experiencing greater stresses than smaller taxa. Whilst 
Suchomimus scales with other theropods, Spinosaurus is a notable outlier and 
experiences much higher magnitudes of cranial stress than would be predicted. 
It may be that when realistic loading parameters are considered, larger 
theropods mitigate potential cranial weakness through concomitant scaling of 
adductor muscle and bite force or through modifications to feeding ecology, 
especially in taxa such as Spinosaurus. Given the 2D nature of these models, 
results and interpretations should be treated with caution, and are at best 
considered predictors of biomechanical performance and feeding ecology, to be 
tested in the future with more appropriate 3D finite element models.