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Cretaceous marine reptiles from Japan

From: Ben Creisler

A new online paper:

T. Sato, T. Konishi, R. Hirayama & M.W. Caldwell (2012)
A review of the Upper Cretaceous marine reptiles from Japan.
Cretaceous Research (advance online publication)

Taxonomy and stratigraphic distribution of the Upper Cretaceous marine
reptiles from Japan are reviewed. Remains of the Chelonioidea (sea
turtles), Mosasauridae, and Plesiosauria are known in various parts of
Japan, including the holotypes of the dermochelyid Mesodermochelys
undulatus, mosasaurine Mosasaurus hobetsuensis and M. prismaticus,
tylosaurine Taniwhasaurus mikasaensis, and elasmosaurid Futabasaurus
suzukii. Less diagnostic materials of other groups such as
protostegiids, plioplatecarpines, polycotylids, pliosauroids, were
also collected. Mesodermochelys dominates the chelonioid fauna, and in
comparison with European and North American faunas, suggests a rather
restricted geographical distribution of chelonioid species during the
Late Cretaceous. The mosasaurid records support the world-wide trend
of increasingly mosasaurine-dominated post-Santonian assemblages, and
demonstrate suprageneric-level compositional changes in the
northwestern Pacific through time. Elasmosaurid fossils are known from
all stages of the Upper Cretaceous in Japan and indicate their
continuous presence in the northwestern Pacific. Polycotylid remains
are fewer in number and limited to the lower Upper Cretaceous.
Pliosauroid specimens are even rarer but raise the upper limit of the
stratigraphic range of the group in Northern Pacific to the Turonian.