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Turiasaurus (Sauropoda) skull

From: Ben Creisler

A new online paper:

Rafael Royo-Torres & Paul Upchurch (2012)
The cranial anatomy of the sauropod Turiasaurus riodevensis and
implications for its phylogenetic relationships.
Journal of Systematic Palaeontology (advance online publication)

The skull of Turiasaurus is known from a nearly complete posterior
section (e.g. braincase, skull roof, quadrates and left mandible) and
fragments of the snout (e.g. portions of premaxilla, maxilla, nasal
and lacrimal). Skull material of the holotypic individual was
discovered in close association. Comparisons with other sauropods
suggest that the Turiasaurus skull most closely resembled those of
Jobaria, Camarasaurus and Mamenchisaurus youngi, possessing large
spatulate teeth, enlarged and partially retracted external nares, and
a broadly rounded muzzle. The list of autapomorphies for Turiasaurus
is augmented by the new cranial data, including features such as: (1)
a shelf-like projection of bone from the medial surface of the distal
end of the maxillary ascending process; and (2) a rounded boss-like
area on the lateral surface of the jugal. There are also unusual
character states, such as the excavation of the posterior surfaces of
the basal tubera (present in Turiasaurus and Losillasaurus) that
probably have a wider phylogenetic significance. Phylogenetic
analyses, using two different datasets, support the view that
Turiasaurus, Losillasaurus and Galveosaurus form a monophyletic
Turiasauria clade that lies just outside of Neosauropoda. The addition
of the new cranial data slightly strengthens the support for this
topology, but the relationships of other taxa (such as Jobaria) become
less stable. The Turiasauria might represent a distinct group of
non-neosauropods with a wide geographic distribution across Europe and
Africa during the Late Jurassic.