Tylosaurinae
Tylosaurinae Temporal range: Late Cretaceous
| |
---|---|
Tylosaurus nepaeolicus mounted skeleton in the Rocky Mountain Dinosaur Resource Center in Woodland Park, Colorado
| |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Clade: | †Mosasauria |
Superfamily: | †Mosasauroidea |
Family: | †Mosasauridae |
Clade: | †Russellosaurina |
Subfamily: | †Tylosaurinae Williston, 1895[1] |
Genera | |
The Tylosaurinae are a subfamily of mosasaurs,[2] a diverse group of Late Cretaceous marine squamates. Members of the subfamily are informally and collectively known as "tylosaurines" and have been recovered from every continent except for South America.[3] The subfamily includes the genera Tylosaurus, Taniwhasaurus, and Kaikaifilu, although some scientists argue that only Tylosaurus and Taniwhasaurus should be included.[4][5]
Tylosaurines first appeared in the Coniacian[6] and gave rise to some of the largest mosasaurs within the genera Tylosaurus and Hainosaurus which came to dominate as apex predators in marine ecosystems throughout the Santonian and Campanian, but appear to have been largely replaced by large mosasaurines, such as Mosasaurus, by the end of the Maastrichtian.[7] Nevertheless, the subfamily survived to the end of the Cretaceous, covering a period lasting approximately twenty million years.
The etymology of this group derives from the genus Tylosaurus (Greek tylos = "knob" + Greek sauros = "lizard").
Description
In general, tylosaurines were large-bodied marine lizards armed with sturdy, conical teeth and an elongated premaxilla and extensions of the dentaries that do not bear teeth to the very end such as is found in other genera of mosasaurs. Cope's original concept of a "battering ram" snout is not supported by fossil evidence. Stomach contents from a tylosaur recovered in
Lingham-Soliar suggested that tylosaurines were not among the fastest swimming nor the strongest mosasaurids. However, they are lightly built, having greatly reduced the weight of their bodies and possessing relatively small
Russell (1967, pp. 170
Species and taxonomy
Tylosaurinae[4]
- Tylosaurus
- T. proriger
- T. nepaeolicus (=T. kansasensis)
- T. pembinensis
- T. gaudryi
- T. saskatchewanensis
- T. ivoensis
- T. iembeensis
- Hainosaurus (=Tylosaurus?)
- H. bernardi
- Taniwhasaurus
- T. oweni (=Tylosaurus haumuriensis)
- T. antarcticus
- Kaikaifilu
- K. hervei
References
- ^ Williston, S. W. 1895. New or little-known extinct vertebrates. Kansas University Quarterly 6:95-98.
- ^ Williston, S. W. 1897. Range and distribution of the mosasaurs with remarks on synonymy. Kansas University Quarterly 4(4):177-185.
- ^ "Fossilworks: Tylosaurinae". fossilworks.org. Retrieved 17 December 2021.
- ^ S2CID 85513442.
- ^ Garvey, S.T. (2020). "A New High-latitude Tylosaurus (Squamata, Mosasauridae) from Canada with Unique Dentition". Cincinnati, Ohio: University of CinCinnati. pp. 1–136.
- ^ Everhart MJ. 2005b. Earliest record of the genus Tylosaurus (Squamata; Mosasauridae) from the Fort Hays Limestone (Lower Coniacian) of western Kansas. Transactions 108 (3/4): 149-155.
- .
- ^ Martin JE, Bjork PR. 1987. Gastric residues associated with a mosasaur from the late Cretaceous (Campanian) Pierre Shale in South Dakota. Dakoterra 3:68-72.
- ^ Sternberg CH. 1922. Explorations of the Permian of Texas and the chalk of Kansas, 1918. Transactions of the Kansas Academy of Science 30(1):119-120. (Papers - Fifty-first annual meeting, 1919), State Printer, Topeka.
- ^ Everhart MJ. 2004. Plesiosaurs as the food of mosasaurs; new data on the stomach contents of a Tylosaurus proriger (Squamata; Mosasauridae) from the Niobrara Formation of western Kansas. The Mosasaur 7:41-46.
- ^ Russell DA, 1967. Systematics and morphology of American mosasaurs. Peabody Museum of Natural History, Yale University, Bulletin 23.
Further reading
- Bell, G. L. Jr., 1997. A phylogenetic revision of North American and Adriatic Mosasauroidea. pp. 293–332 In Callaway J. M. and E. L Nicholls, (eds.), Ancient Marine Reptiles, Academic Press, 501 pp.
- Lindgren, J. et. Siverson, M. 2002.Tylosaurus ivoensis: a giant mosasaur from the early Campanian of Sweden. Royal Society of Edinburgh Transactions: Earth Sciences Vol. 93(1):73-93.
- Russell, D. A. 1970. The vertebrate fauna of the Selma Formation of Alabama, Part VII, The mosasaurs, Fieldiana: Geology Memoirs 3(7):369-380.