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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.