Yaguarasaurus
Encyclopedia
Yaguarasaurus was a genus of mosasaur
Mosasaur
Mosasaurs are large extinct marine lizards. The first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764...

 from the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

 (Turonian
Turonian
The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous epoch, or a stage in the Upper Cretaceous series. It spans the time between 93.5 ± 0.8 Ma and 89.3 ± 1 Ma...

) period of Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...

, South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

. The remains discovered (a skull articulated, some vertebrae and ribs) were defined as a new genus and species of the tribe Plioplatecarpini, Yaguarasaurus columbianus, by the Colombian paleontologist María Páramo, former director of the Museo de Geología José Royo y Gómez of INGEOMINAS in Bogota
Bogotá
Bogotá, Distrito Capital , from 1991 to 2000 called Santa Fé de Bogotá, is the capital, and largest city, of Colombia. It is also designated by the national constitution as the capital of the department of Cundinamarca, even though the city of Bogotá now comprises an independent Capital district...

. The remains were found in a limestone bench (Upper Turonian) of the Villeta Formation near Yaguará, in the site called Cueva Rica (Huila
Huila Department
Huila is one of the departments of Colombia. It is located in the southwest of the country, and its capital is Neiva.-Geography:The south of the department is located in the Colombian Massif...

). Its name means "Yaguará lizard of Colombia", and measured about 5 meters long, with a cranial length of 47 cm. Yaguarasaurus were a close relative of Russellosaurus
Russellosaurus
Russellosaurus is a basal mosasauroid from the Upper Cretaceous of North America. The genus was described from a skull discovered in an exposure of the Arcadia Park Shale at Cedar Hill, Dallas County in south-central Texas...

 coheni
and Tethysaurus
Tethysaurus
Tethysaurus was a genus of mosasaur from the Early Turonian period. The only species is Tethysaurus nopscai. The name means "Tethys' lizard of Nopsca", a reference to the Greek goddess of the sea Tethys and to the Hungarian paleontologist Baron Ferenc Nopsca, who made...

 nopscai
, a group that could be a basal clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 to the division between Tylosaurinae
Tylosaurinae
Tylosaurinae is a subfamily of mosasaurs, a diverse group of Late Cretaceous marine lizards.Russell defined the Tylosaurinae as follows: "Large rostrum present anterior to premaxillary teeth. Twelve or more teeth in dentary and maxilla. Cranial nerves X, XI, and XII leave lateral wall of...

 and Plioplatecarpinae subfamilies, called Russellosaurina.

This reptile is a member of the family of marine lizards Mosasauridae characteristic of Middle and Upper Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

, with global distribution, but in South America known only through isolated remains (Price, 1957, Pierce and Welles, 1959 ; Bonaparte, 1978; Ameghino, 1918). The new mosasaur of Yaguará discovered, is now the most complete material known in South America.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK