Named By: A. G. Sennikov & M. S. Arkhangelsky - 2010.
Classification: Chordata, Reptilia, Sauropterygia, Plesiosauria, Elasmosauridae.
Species: A. karnoushenkoi (type).
Known locations: Russia, Franz Josef Land - Wilczek Formation.
Time period: Norian of the Triassic.
Fossil representation: Partial skeleton.
Alexeyisaurus was described from partial remains,
it seems that
further material was actually present at the site of its discovery.
Still, the material recovered is enough to suggest that
Alexeyisaurus is one of the earliest known
the group of plesiosaurs that had proportionately much longer necks
than the more ‘standard’ plesiosaurs. Like others of this group
Alexeyisaurus would have been a piscivorous hunter
of fish and possibly
squid which would have been caught by the mouth which contained long
thin teeth, perfectly suited to catching this type of prey.
Additionally the presence of a basal elasmosaurid like Alexeyisaurus
during the late Triassic not only helps prove that they lived
alongside other earlier plesiosaurs, but that they survived the
extinction event that marks the end of the Triassic. This was a
particularly bad one for oceanic life, and would not be seen on
similar level until the end of Cretaceous extinction that saw an end to
all of the large marine reptiles, as well as the pterosaurs
Alexeyisaurus was named in memory of the palaeontologist Aleksei Savvich Arkhangelsky.