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Nearly complete ankylosaurid dinosaur skeleton from Mongolia

From: Ben Creisler

A new paper:

Victoria M. Arbour & Philip J. Currie (2013)
The taxonomic identity of a nearly complete ankylosaurid dinosaur
skeleton from the Gobi Desert of Mongolia.
Cretaceous Research 46: 24–30

Mongolian Paleontological Center (MPC) 100/1305 is one of the most
complete ankylosaurid skeletons ever collected, and includes much of
the postcranial skeleton and numerous in situ osteoderms. This
specimen has been referred to Saichania chulsanensis, based on the
similarity of the skull compared to the holotype of Saichania, MPC
100/151. However, MPC 100/1305 does not include a skull, and so
referral of MPC 100/1305 to Saichania must be based on postcranial
characters. Comparison of the postcrania of MPC 100/1305 and MPC
100/151 reveals several differences in the scapula, humerus, and
metacarpals, indicating that MPC 100/1305 should not be referred to
Saichania. Additionally, although it was previously reported that MPC
100/1305 was collected from the Baruungoyot Formation at Khulsan in
Mongolia, collection records indicate that this specimen was instead
collected from the Djadokhta Formation at Zamyn Khond. Two
ankylosaurid species are known from the Djadokhta Formation of
Mongolia and China, Pinacosaurus grangeri and P. mephistocephalus.
There are no diagnostic characters in MPC 100/1305 that can be used to
refer this specimen to P. grangeri or P. mephistocephalus, and there
are a few differences between MPC 100/1305 and Pinacosaurus, such as
the number of caudal vertebrae, and morphology of the coracoid, which
have uncertain taxonomic implications. At present, MPC 100/1305 is
best referred to Ankylosauridae indet., or cf. Pinacosaurus, based on
its generally congruent morphology with Pinacosaurus and its
provenance from the Djadokhta Formation, in which Pinacosaurus is the
only recognized ankylosaurid taxon.