Eotitanosuchus ("dawn giant crocodile") is an extinct genus of whose were found in the town of Ochyor in Perm Krai, Russia. It lived about 267 million ago. The only species is Eotitanosuchus olsoni.
Description
Eotitanosuchus is known from a single large skull without a lower jaw. The
skull was , but the overall length may have been over , possibly up to and more than in weight for adult specimens.
Like
Biarmosuchus tener, it was primitive in that, though it was a predator, the temple opening behind the eye was small, giving it a weak
Biting. The temple was, however, larger at the top than in other
.
Paleobiology
Eotitanosuchus fossils were found in the Perm (or Cis-Urals) region of Russia.
Eotitanosuchus was without doubt a dominant animal of its environment. Found preserved in flood deposits (once coastal bogs) containing many skeletons of estemmenosuchids, it has been suggested that this large predator was an excellent swimmer, possibly semi-aquatic or frequenting marshy ground. This, however, is just speculation.
Classification
Eotitanosuchus is often grouped with the
Phthinosuchus and the
Biarmosuchus. In fact, Ivakhnenko (1999) argues that
Biarmosuchus tener and
Eotitanosuchus olsoni are the same organism, which would eliminate the
Eotitanosuchidae as a separate taxon, though this conclusion does not seem to have been widely accepted. Regardless of the eventual outcome of this debate, Ivakhnenko's paper does seem to show that
Eotitanosuchus is very similar to
Biarmosuchus. Further, given the rather close similarity between
Eotitanosuchus and later therapsids, this observation supports the view that Biarmosuchia is
Paraphyly. Others view
Eotitanosuchus as quite distinct from other basal therapsids and perhaps closer to the
Gorgonopsia but gorgonopsian specializations are either not present in
Eotitanosuchus or, as is more often the case, the state of the characters is unknown. This genus is characterized by many primitive features of the septomaxilla, the postorbital, the parietal, the interparietal, the basioccipital, the quadrate rami of the pterygoid and the
of the skull. The length of the dorsal process of the
premaxilla (front jawbone) and the postorbital twisting (rear side of the skull) constitute specializations that indicate it is not a direct gorgonopsian ancestor. These features, however, are shared by the
anteosaur and
Biarmosuchus lineages.
See also
-
Patricia Vickers-Rich and Thomas H. Rich, The Great Russian Dinosaurs, Gunter Graphics, 1993, pg. 28.
External links
