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Marine reptiles from Chile



From: Ben Creisler
bcreisler@gmail.com

Two papers about fossils of marine reptiles found in Chile:

Judith Pardo-Pérez, Eberhard Frey, Wolfgang Stinnesbeck, Marta S.
Fernández, Luis Rivas, Christian Salazar and Marcelo Leppe (2012)
An ichthyosaurian forefin from the Lower Cretaceous Zapata Formation
of southern Chile: implications for morphological variability within
Platypterygius.
Palaeobiodiversity and Palaeoenvironments (advance online publication)
DOI: 10.1007/s12549-012-0074-8
http://www.springerlink.com/content/143766631848552q/

Expeditions to the Tyndall Glacier (Torres del Paine National Park,
South Chile) in 2009 and 2010 recovered an articulated ichthyosaurian
forefin that displayed traits consistent with Platypterygius. The
combination of features observed in this forefin has not been observed
in other Platypterygius species, i.e.: (1) one preaxial row and three
or even four postaxial rows; (2) the distal articulation of ulna with
metacarpal five; (3) the shape and the articulation context of distal
carpal three, metacarpal three and four; (4) the hexagonal shape of
the intermedium; and (5) the presence of only two distal articular
facets on the humerus. Nevertheless, the forefin is not referred to a
new species, because it was found isolated and no other diagnostic
skeletal elements are present. The forefin presented here is the first
complete and articulated forefin of a Platypterygius from the South
Pacific margin, and together with other ichthyosaurs from the Tyndall
area, represents the southernmost occurrence of Early Cretaceous
ichthyosaurs in the Americas.

===
Rodrigo A. Otero, James F. Parham, Sergio Soto-Acuña, Paulina
Jimenez-Huidobro, David Rubilar-Rogers (2012)
Marine reptiles from Late Cretaceous (early Maastrichtian) deposits in
Algarrobo, central Chile.
Cretaceous Research 35 :124–132
http://dx.doi.org/10.1016/j.cretres.2011.12.003
http://www.sciencedirect.com/science/article/pii/S0195667111002035


We report new specimens of Late Cretaceous (early Maastrichtian)
reptiles collected from Algarrobo, central Chile. The Algarrobo
fossils include the northernmost occurrence of marine turtles,
articulated plesiosaur remains, and mosasaur teeth recognized in the
Weddellian Biogeographic Province. The presence of articulated
material and teeth of elasmosaurid plesiosaurs, mosasaur teeth, and
postcranial remains of cf. dermochelyid sea turtles re-emphasizes an
emerging picture of the composition of Maastrichtian marine reptiles
in the Pacific Basin. The fossil reptiles suggest that the Algarrobo
strata were deposited on a shallow marine shelf. Proximity to the
coast is indirectly suggested by the presence of fossil wood.