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Sauropod diversity in Late Cretaceous Southwestern Europe

From: Ben Creisler

A new online paper:

B. Vila, À. Galobart, J.I. Canudo, J. Le Loeuff, J. Dinarès-Turell, V.
Riera, O. Oms, T. Tortosa & R. Gaete (2012)
The diversity of sauropod dinosaurs and their first taxonomic
succession from the latest Cretaceous of southwestern Europe: Clues to
demise and extinction.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)

Southwestern Europe is a key setting to evaluate the diversity of
non-avian dinosaurs before the end of the Cretaceous (below the K-Pg
boundary). The ancient Ibero-Armorican Island, encompassing the
current regions of North-East Iberia and South France, provides a
substantial record of sauropod fossils. The study of multiple sauropod
femora from localities where upper Campanian to uppermost
Maastrichtian successions are both exposed, together with the
integration of the information gathered from previously known
localities has allowed the biodiversity of sauropods to be reassessed
within a precise and clear chronostratigraphic framework. From the
studied sample several titanosaur forms have been distinguished
including a gracile and small-sized titanosaur (Lirainosaurus
astibiae), a robust medium-sized titanosaur (Ampelosaurus atacis), a
gracile medium-sized titanosaur (Atsinganosaurus velauciensis), and
five other indeterminate but distinct titanosaurs, which span the late
Campanian through the entire Maastrichtian. The youngest of these
occurs in the uppermost part of palaeomagnetic chron C30n in the
latest Maastrichtian (~ 0.4–1 Ma before the K-Pg boundary),
representing the youngest sauropod yet documented in Eurasia. The
pattern of diversity on the Ibero-Armorican Island rules out a decline
in sauropod diversity at the very end of the Cretaceous. As with other
regions during the Late Cretaceous, the abundance and quality of the
sauropod fossil record is probably influenced by multiple biases
(sampling, ecological, environmental).