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Gulosaurus, new Triassic ichthyosaur from British Columbia

From:  Ben Creisler

A paper in the new JVP:

Robin S. Cuthbertson, Anthony P. Russell & Jason S. Anderson (2013)
Cranial morphology and relationships of a new grippidian
(Ichthyopterygia) from the Vega-Phroso Siltstone Member (Lower
Triassic) of British Columbia, Canada.
Journal of Vertebrate Paleontology 33(4): 831-847

In 1989, TMP 89.127.3, a basal ichthyopterygian, was collected as a
counterpart slab from the Vega-Phroso Siltstone Member (Lower
Triassic) of the Sulphur Mountain Formation in east-central British
Columbia, Canada. Previous investigations of its postcranial skeleton
resulted in ambiguous taxonomic affinities, with it being identified
as either Grippia cf. longirostris or Parvinatator wapitiensis. More
recently, the part slab of TMP 89.127.3 was collected and prepared,
revealing important new cranial data that permits its systematic
relationships to be more thoroughly assessed and previously proposed
taxonomic affinities to be tested. By integrating both cranial and
postcranial data, phylogenetic analysis recovers TMP 89.127.3 and
Grippia as members of Grippidia, nested within Eoichthyosauria. TMP
89.127.3 can be distinguished from Grippia by possessing the following
autapomorphies: metacarpal I with a notched peripheral shaft;
cylindrical anterior teeth with a crown shape index >5.0; and a
postfrontal-frontal contact at the rostral limit of the anterior
margin of the supratemporal terrace. A new taxon, Gulosaurus helmi, is
erected to accommodate this suite of features. The placement of
Gulosaurus helmi within Grippidia reaffirms the Early Triassic
distribution of this clade to include western and northern Laurasia,
which is represented by outcrop in present-day Canada and Norway
(Spitzbergen), respectively.