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Dolerosaurus, new phytosaur from Triassic of Austria

From: Ben Creisler

A paper in the new JVP:

Richard J. Butler (2013)
‘Francosuchus’ trauthi is not Paleorhinus: implications for Late
Triassic vertebrate biostratigraphy.
Journal of Vertebrate Paleontology 33(4): 858-864

A rostrum fragment from the marginal marine upper Lunz Formation of
Austria (early Late Triassic: late Carnian) was previously identified
as a new species of phytosaurian archosauriform, ‘Francosuchus’
trauthi. ‘Francosuchus’ trauthi was subsequently synonymized with the
non-phytosaurid phytosaur Paleorhinus, and this synonymy was used as
evidence to correlate the ‘Paleorhinus biochron’ and the Otischalkian
land-vertebrate faunachron to the marine timescale. Here, I provide a
redescription of ‘Francosuchus’ trauthi and document anatomical
features that differ substantially from all known species of
non-phytosaurid phytosaur. There is no evidence to support synonymy of
‘Francosuchus’ trauthi with Paleorhinus, and no unambiguous features
to support a phytosaurian identification. However, ‘Francosuchus’
trauthi possesses a unique combination of characters that distinguish
it from all other Triassic tetrapods, and necessitates referral of the
species to a new genus, Dolerosaurus, gen. nov. Rejection of the
proposed synonymy between ‘Francosuchus’ trauthi and Paleorhinus means
that the ‘Paleorhinus biochron’ cannot be tied to the marine late
Carnian as previously suggested, and provides further evidence of the
problems inherent in attempting to correlate the terrestrial Triassic
to the marine timescale.