Plotosaurus

Taxobox
name = "Plotosaurus"
fossil_range = Late Cretaceous
regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Squamata
subordo = Scleroglossa
familia = Mosasauridae
subfamilia = Mosasaurinae
genus = "Plotosaurus"
genus_authority = Camp, 1951
subdivision_ranks = Species
subdivision =
* "P. bennisoni" (type)
(Camp, 1942) Camp, 1951
* "P. tuckeri"
(Camp, 1942) Camp, 1951
synonyms =
* "Kolposaurus" Camp, 1942
* "Garzasaurus" Anderson, 1943
(nomen nudum)

"Plotosaurus" ("swimmer lizard") is an extinct genus of mosasaur from the Upper Cretaceous (Maastrichtian) of Fresno County, California. Originally named "Kolposaurus" (meaning "bay lizard") by Berkeley paleontologist Charles Lewis Camp in 1942, it was changed to "Plotosaurus" in 1951 when Camp discovered the name had already been assigned to a type of nothosaur.Plotosaurs possessed several adaptations to marine life not seen in other mosasaurs. Their narrower flippers, large tail fins and streamlined fusiform body shape probably enabled them to be faster swimmers than most other mosasaurs Fact|date=February 2008. They also had relatively large eyes for keen eyesight. Based on cladistic analysis, plotosaurs are considered to be the most derived branch of mosasaur evolution.

The type species, "P. bennisoni", was named for Allan Bennison, a fossil hunter who discovered the first remains in 1937. It was around 9 meters (30 ft) long, and was the first known mosasaur from California (a year previously, Bennison had also discovered the state's first dinosaur, "Saurolophus").

A second species, "P. tuckeri", was also found in 1937 by Frank Paiva and Professor William M. Tucker. Although, not quite as advanced in aquatic adaptations as "P. bennisoni" it was about 40% larger, reaching lengths of around 13 meters (over 42 ft) Fact|date=February 2008.

References

* Camp, C.L. 1942. "California Mosasaurs." Memoirs of the University of California 13. Berkeley and Los Angeles: University of California Press.

* Camp, C.L. 1951. "Plotosaurus", a new generic name for "Kolposaurus" Camp, preoccupied. "Journal of Paleontology" 25: 822.

* Hilton, R.P. 2003. "Dinosaurs and Other Mesozoic Reptiles of California". Berkeley and Los Angeles: University of California Press. ISBN 0-520-23315-8

External links

*Mosasauridae Translation and Pronunciation Guide [http://www.dinosauria.com/dml/names/mosa.html#P]
*Natural History Museum of Los Angeles County [http://www.nhm.org/journey/prehist/marine/plotosaurus.html]
*UCMP Paleontology Portal [http://www.paleoportal.org/index.php?globalnav=fossil_gallery&sectionnav=detail&submission_id=687&taxon_id=&state_id=&period_id=18&assemblage_id=&last_section=search]