During
the Late Cretaceous rising sea levels caused the Atlantic Ocean to
cover much of what is now Patagonia, laying down a succession of
marine sediments that are collectively known as the Malargüe Group.
The lowermost deposits of this group are the sediments of the
Loncoche Formation, which are interpreted as having been laid down in
coastal lagoons, estuaries, tidal flats and deltaic to shallow marine
environments along a narrow, elongate embayment. These sediments have
produced a range of marine and terrestrial Vertebrate fossils,
including Fish, Turtles, Tortoises, Theropods, Titanosaurs and
Plesiosaurs.
In a
paper published in the journal Cretaceous Research on 21 September
2016, Marcelo de la Fuente, Ignacio Maniel, and Juan Marcos Jannello
of the Grupo Vinculado al Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales at the Museo de Historia Natural deSan Rafael and The National Scientific and Technical Research Councilof Argentina, Juliana Sterli, also of The National Scientific and
Technical Research Council of Argentina, and of the MuseoPaleontológico EgidioFeruglio, Bernardo Gonzalez Riga, again of The National Scientific
and Technical Research Council of Argentina, and also of the
Laboratorio de Dinosaurios at the Universidad Nacional de Cuyo, and
Fernando Novas of the Laboratorio de Anatomía Comparada y Evolución
de los Vertebrados at the Museo Argentino de Ciencias Naturales“Bernardino Rivadavia”, and also of The National Scientific and
Technical Research Council of Argentina describe a new species of
Turtle from the Ranquil-Có
exposure of the Loncoche Formation in Southern Mendoza
Province, Argentina.
The new
species named Mendozachelys wichmanni,
where 'Mendozachelys'
comes from 'Mendoza' the province where it was discovered, plus
'chelys', which is Greek for Turtle. It is described from a
single specimen excavated in 1990 by a team lead by palaeontologist
José Bonaparte, and given
a preliminary description in a paper by the same authors presented at
the 5th Turtle Evolution Symposium in Rio de Janeiro in 2015 and
published in the journal PeerJ. The specimen is largely complete, if
somewhat flattened, and was articulated when discovered, although it
was disassembled during preparation. It is calculated to have had a
shell length of about 190 mm when alive, and a histological examination of the bones of the shell suggests an aquatic or semi-aquatic lifestyle.
Mendozachelys
wichmanni gen. et sp. nov. Loncoche Formation (Upper Cretaceous).
Carapace dorsal view: (A) Photograph; (B) Drawing. De la Fuente et al. (2016).
See also...
Follow
Sciency Thoughts on Facebook.