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Oh... Barracuda!



This just out today:

Jiang, D.-Y., W.-C. Hao, M. W. Maisch, A. T. Matzke & Y.-L. Sun. 2005. A
basal mixosaurid ichthyosaur from the Middle Triassic of China.
Palaeontology 48(4): 869-882.

"New specimens of a mixosaurid ichthyosaur are described from the People's
Republic of China. They consist of an almost complete skull, forefin and
shoulder girdle of a single individual, and a second partial skull from the
Anisian Guanling Formation of Guizhou Province that belongs to the same
taxon. A phylogenetic analysis shows this species to be the sister-taxon of
all other mixosaurids. It is distinguished from Mixosaurus, Contecotpalatus
and Phalarodon by features of its dentition and cranial morphology. There is
only one maxillary tooth row. The posterior maxillary teeth are blunt and
rounded, and much wider than the premaxillary teeth, but they are not
strongly elongated anteroposteriorly. The teeth are subthecodontously
implanted. The postorbital skull segment is long. The jugal-quadratojugal
notch is deep and these two elements remain separated externally. The
postorbital separates supratemporal and postfrontal. There are no postaxial
ossifications of the forefin. Autapomorphies include a long ventral process
of the postorbital lamina of the postorbital as well as characteristic
morphologies of the coracoid and humerus. The material is therefore clearly
distinguished from other known mixosaurids. It can be referred, on the basis
of the features of the humerus and coracoid, to Mixosaurus maotaiensis
Young, 1965. As it is generically distinct from Mixosaurus, a new generic
name, Barracudasaurus gen. nov. is proposed. The phylogenetic relevance of
the external separation of jugal and quadratojugal in some Triassic
ichthyosaurs is discussed and it is concluded that it does not demonstrate
the initial presence of a lower temporal fenestra in ichthyosaurs. The new
material suggests that mixosaurids could have also originated in the Eastern
rather than the Western Tethys, as previously assumed."

    Cheers,

        Christopher Taylor