- Selmasaurus
Taxobox
name = "Selmasaurus"
fossil_range =Late Cretaceous
regnum =Animal ia
phylum = Chordata
classis =Sauropsid a
ordo =Squamata
familia =Mosasauridae
subfamilia =Plioplatecarpinae
genus = "Selmsaurus"
species = "S. russelli"
binomial = "Selmasaurus russelli"
binomial_authority = Wright et Shannon,1988 "Selmasaurus" is a genus of medium-sized plioplatecarpine
mosasaur from the UpperCretaceous Mooreville Chalk Formation (Campanian ) of westernAlabama (United States). First recognized bygeologist Samuel Wayne Shannon in his 1975 Master's thesis, "Selected Alabama Mosasaurs," the taxon remained a "nomen nudum " until it was officially described in 1988 ("A new plioplatecarpine mosasaur (Squamata , Mosasauridae) from Alabama", Journal of Vertebrate Paleontology, Vol. 8, No. 1, 31 March 1988) in an article coauthored by Shannon and paleontologistCaitlin R. Kiernan . The type specimen, formerly reposited at the Geological Survey of Alabama and cataloged as GSATC 221, was transferred in 2005 to the Alabama Museum of Natural History (Tuscaloosa). The holotype consists of a very well-preserved but incomplete and disarticulated skull, the left atlantal neural arch, atlas centrum, and a single neural arch from a cervical vertebra. Preserved skull elements include the frontal, parietal, left ectopterygoid, left jugal, supratemporals, basioccipital and basisphenoid, and quadrates. To date, it is the only known specimen of "Selmasaurus", which contains only a single species "S. russelli" (named in honor of paleontologistDale A. Russell , for his extensive work on mosasaurs).Relationship to other Mosasauroids
Shannon and Kiernan classified "Selmasaurus" as a member of the mosasaur family Plioplatecarpinae, which also includes the genera "Platecarpus", "Plioplatecarpus", and "Ectenosaurus", largely on the "basis of the mode of circulation through the basicarnium." The genus may be most closely related to "Ectenosaurus", though it possesses a much shorter, stouter skull. Additional specimens would greatly expand our understanding of "Selmasaurus russelli".
Cranial kinesis
The mosasaur "Selmasaurus" is notable in that its skull is unusually akinetic. Most mosasurus have skulls which possess "coupled kinesis" (mesokinesis and streptostyly), that is, parts of the jaw can open widely to accommodate large prey.
References
*Wright, K. R. and S. W. Shannon. 1988. Selmasaurus russelli, A new plioplatecarpine mosasaur (Squamata, Mosasauridae) from Alabama. "Journal of Vertebrate Paleontology" 8(1):102-107.
*Russell, D. A. 1967. Systematics and morphology of American mosasaurs. Peabody Museum of Natural History, Yale University, Bulletin 23.
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