Aigialosaurus Explained

Aigialosaurus is an extinct genus of Late Cretaceous marine or semiaquatic lizard classified as part of the family Aigialosauridae within the Mosasauroidea. Exclusively found in deposits of Cenomanian age near Hvar, Croatia, the genus contains one valid species, A. dalmaticus.^[1] According to recent molecular and morphological data, Aigialosaurus is the oldest known member of the lineage leading to large Cretaceous marine reptiles called mosasaurs, a group most closely related to snakes among living squamates.^{[2] [3]} It was a relatively small reptile with a complete specimen measuring long.^[4]

Another primitive mosasauroid, Opetiosaurus, was suggested to represent a second species of Aigialosaurus in 2009, "Aigialosaurus bucchichi",^[5] though this conclusion has not been supported by recent analyses.

Notes and References

1. Madzia, D., Cau, A. (2017). Inferring "weak spots" in phylogenetic trees: application to mosasauroid nomenclature . PeerJ 5:e3782
2. Grigoriev, D. V. (2013). "Redescription of Prognathodon lutugini (Squamata, Mosasauridae)." Proceedings of the Zoological Institute RAS, 317(3): 246-261.
3. Tod W. Reeder, Ted M. Townsend, Daniel G. Mulcahy, Brice P. Noonan, Perry L. Wood Jr., Jack W. Sites Jr., and John J. Wiens. (2015). "Integrated analyses resolve conflicts over Squamate reptile phylogeny and reveal unexpected placements for fossil taxa" PLoS ONE 10(3): e0118199.
4. Bardet. Nathalie. The Cenomanian-Turonian (late Cretaceous) radiation of marine squamates (Reptilia): the role of the Mediterranean Tethys. Bulletin de la Société Géologique de France. 2008. 179. 6. 605–623. 10.2113/gssgfbull.179.6.605.
5. Dutchak, Alex R.; and Caldwell, Michael W. (2009)."A redescription of Aigialosaurus (= Opetiosaurus) bucchichi (Kornhuber, 1901) (Squamata: Aigialosauridae) with comments on mosasauroid systematics". Journal of Vertebrate Paleontology 29 (2): 437-452.