Mosasaurs (from Latin Mosa meaning the 'Meuse river' in the Netherlands, and Greek sauros meaning 'lizard') were serpentine marine reptiles. The first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1778. These ferocious marine predators are now considered to be the closest relatives of snakes, due to cladistic analysis of symptomatic similarities in jaw and skull anatomies. Mosasaurs were not dinosaurs but lepidosaurs, reptiles with overlapping scales. These predators evolved from semi-aquatic squamates known as the aigialosaurs, close relatives of modern-day monitor lizards, in the Early Cretaceous Period. During the last 20 million years of the Cretaceous Period (Turonian-Maastrichtian), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators.
Known genera include Clidastes, Mosasaurus, Prognathodon, Globidens, Plotosaurus, Plesiotylosaurus, Carinodens, Dallasaurus, Igdamanosaurus, Halisaurus, Tylosaurus, Platecarpus, Selmasaurus, Plioplatecarpus, Amphekepubis, Goronyosaurus, Liodon, Moanasaurus, Pluridens, Lakumasaurus, Yaguarasaurus, Eonatator, Hainosaurus, Tethysaurus, Angolasaurus, Kourisodon and Russellosaurus.
DescriptionThe first publicized discovery of a fossil mosasaur preceded any dinosaur fossil discoveries and drew the Age of Enlightenment's attention to the existence of fossilized animals; the specimen was discovered in 1780 by quarry-workers in a subterranean gallery of a limestone quarry; they quickly alerted Doctor C. K. Hoffman, a surgeon and fossil-hunter in the Dutch city of Maastricht, although rights of ownership lay with a canon of Maastricht cathedral, as owner of the overlying land.
Dr. Hoffman's correspondence among men of science made the find famous. When the Revolutionary forces occupied Maastricht, the carefully-hidden fossil was uncovered, betrayed, it is said, by a case of wine, and transported to Paris, where Georges Cuvier was able to describe it for science, although le grand animal fossile de Maastricht was not actually described as a Mosasaur ('Meuse reptile') until 1822 and not given its official name, Mosasaurus hoffmanni, until 1829. Several sets of mosasaur remains, that had been discovered earlier at Maastricht but were not identified as mosasaurs until the nineteenth century, have been on display in the Teylers Museum, Haarlem, since about 1770.
The Maastricht limestone beds were rendered so famous by the Mosasaur discovery that they have given their name to the final six-million-year epoch of the Cretaceous, the Maastrichtian.
Evolutionary antecedentsBased on features such as the loosely-hinged jaw, modified/reduced limbs and probable locomotion, many researchers believe that snakes share a common marine ancestry with mosasaurs, a suggestion advanced in 1869, by Edward Drinker Cope, who coined the term "Pythonomorpha" to unite them. The idea lay dormant for more than a century, to be revived in the 1990s. Recently, the discovery of Najash rionegrina, a fossorial snake from South America cast doubt on the marine origin theory.
On 2005-11-16, research reported in Netherlands Journal of Geosciences, confirmed that the recently uncovered Dallasaurus turneri is an early link between land-based monitor lizards (such as the Komodo dragon) and the aquatic mosasaurs.
In popular cultureMosasaurs appear in the BBC television series Sea Monsters. Mosasaurs also feature heavily in the ITV television series Primeval. In this show, the mosasaurs are depicted incorrectly as having skin more similar to a crocodile's.
A highly evolved mosasaur appeared in an episode of Godzilla: The Series. It was inhabiting Loch Ness as the legendary Loch Ness Monster.
The IMAX 3D film "Sea Monsters" features mosasaurs (including Tylosaurus) with detailed animated recreations of their movements and activities.
Alleged living mosasaursAlthough paleontologists have determined that all mosasaurs went extinct around the same time as the dinosaurs, and there is no fossil evidence of them beyond the end of the Cretaceous (Maastrichtian), some cryptozoologists feel that sporadic reports of crocodile-like sea serpents may be surviving mosasaurs . The Taniwha of Māori lore has also been connected to mosasaurs by journalists . However, there is no scientific evidence of any mosasaur remains since the end of the Cretaceous, 65 million years ago.
- Family Mosasauridae
- Subfamily Tylosaurinae
- Subfamily Plioplatecarpinae
- Subfamily Mosasaurinae
- Subfamily Halisaurinae
- Palaeos: Vertebrates: Mosasaurs
- BBC Science and Nature: Mosasaurs
- Mike Everhart and David Lewis, "Mesozoic marine monsters of the Mangahouanga": New Zealand fossil fauna
- Mike Everhart, "A day in the life of a Mosasaur": life in the Sea of Kansas, illus. by Carl Buell
- Mike Everhart, "Mosasaurus hoffmani" until 1829.
- Mosasaurus maximus mounted skeleton at University of Texas Memorial Museum
- Canadian Fossil Discovery Centre
- "The Mosasaur of Maastricht" by Hennie Reuvers in Crossroads web magazine
mosasaur in Bulgarian: Мозазаври
mosasaur in Catalan: Mosasaure
mosasaur in Danish: Mosasaur
mosasaur in German: Mosasaurier
mosasaur in Spanish: Mosasauridae
mosasaur in Croatian: Mozasauri
mosasaur in Italian: Mosasauridae
mosasaur in Hungarian: Mosasauridae
mosasaur in Dutch: Mosasauridae
mosasaur in Polish: Mozazaury
mosasaur in Portuguese: Mosassauro
mosasaur in Slovak: Mosasauridae
mosasaur in Swedish: Mosasaurier
mosasaur in Chinese: 滄龍科