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Titanosaur material from Upper Cretaceous of Uzbekistan

Ben Creisler

A new online paper (no new taxa named):

Hans-Dieter Sues, Alexander Averianov, Ryan C. Ridgely & Lawrence M.
Witmer (2015)
Titanosauria (Dinosauria, Sauropoda) from the Upper Cretaceous
(Turonian) Bissekty Formation of Uzbekistan.
Journal of Vertebrate Paleontology (advance online publication)

Exposures of the Bissekty Formation (Upper Cretaceous: middle–upper
Turonian) at Dzharakuduk in the central Kyzylkum Desert of Uzbekistan
have yielded abundant dinosaurian remains. We report here on cranial
and postcranial remains that can be attributed to titanosaurian
sauropods. This material is of considerable interest in view of the
relative scarcity of sauropod fossils from the Upper Cretaceous of
Central Asia. An incomplete braincase originally assigned to the
ceratopsian Turanoceratops tardabilis actually belongs to a derived
titanosaurian. It shares a number of features (including broad basal
tubera and presence of wide depression between basal tubera) with
braincases of various derived titanosaurian taxa from Asia and South
America. Computed tomographic (CT) scanning of the braincase permitted
digital reconstruction of a partial endocast. Overall, this endocast
resembles those of other sauropods, although the pituitary fossa is
considerably swollen. As in other derived titanosaurians, the abducens
nerve passed lateral to the pituitary fossa. The inner ear resembles
that of some other titanosaurs in having a very short lateral
semicircular canal and that the anterior semicircular canal is only
slightly longer than the posterior one. Isolated sauropod teeth from
Dzharakuduk have slender, ‘pencil-shaped’ crowns, which often bear
high-angle apical wear facets. The caudal vertebrae are gently
opisthocoelous rather than procoelous, as is typically the condition
on at least the anterior caudals in many other titanosaurs. An
anterior caudal vertebra shows extensive pneumatization of its neural
arch. The sauropod remains from the Bissekty Formation establish the
presence of titanosaurians in Central Asia during the Turonian.