Kronosaurus is an extinct genus of short-necked pliosaur. With an estimated length of 9 to 10.9 meters, it was among the largest pliosaurs, and is named after the leader of the Greek Titans, Kronos. It lived in the Early Cretaceous period. Fossil material has been recovered from the Toolebuc Formation and Wallumbilla Formations (Aptian) of Queensland and New South Wales in Australia, and from the upper Paja Formation in Boyacá, Colombia, and assigned to two species.
Pliosauroidea is an extinct clade of marine reptiles. Pliosauroids, also commonly known as pliosaurs, are known from the Jurassic and Cretaceous periods. The pliosauroids were crocodile-like short-necked plesiosaurs with large heads and massive toothed jaws. They were sauropterygian swimming reptiles, and were not dinosaurs. They originally included only members of the family Pliosauridae, of the order Plesiosauria, but several other genera and families are now also included, the number and details of which vary according to the classification used.
Sauropterygia is an extinct, diverse taxon of aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Triassic before all except for the Plesiosauria became extinct at the end of that period. The plesiosaurs would continue to diversify until the end of the Mesozoic. Sauropterygians are united by a radical adaptation of their pectoral girdle, adapted to support powerful flipper strokes. Some later sauropterygians, such as the pliosaurs, developed a similar mechanism in their pelvis. Uniquely among reptiles, sauropterygians moved their tail vertically like modern cetaceans and sirenians.
Liopleurodon is a genus of large, carnivorous marine reptile belonging to the Pliosauroidea, a clade of short-necked plesiosaurs. The two species of Liopleurodon lived from the Callovian Stage of the Middle Jurassic to the Kimmeridgian stage of the Late Jurassic Period. It was the apex predator of the Middle to Late Jurassic seas that covered Europe. The largest species, L. ferox, is estimated to have grown up to 6.4 metres (21 ft) in length.
Peloneustes is an extinct genus of sauropterygian reptile belonging to the family Pliosauridae. It is known from the Callovian aged deposits of the Oxford Clay Formation of England. With a length of around 3 metres (9.8 ft), it was one of the smallest representatives of the group.
Rhomaleosaurus is an extinct genus of Early Jurassic rhomaleosaurid pliosauroid known from Northamptonshire and from Yorkshire of the United Kingdom. It was first named by Harry Seeley in 1874 and the type species is Rhomaleosaurus cramptoni. It was one of the earliest large marine reptile predators which hunted in the seas of Mesozoic era. Its length was about 7 m (23 ft) long. Like other pliosaurs, Rhomaleosaurus fed on ichthyosaurs, ammonites and other plesiosaurs.
Pliosaurus is an extinct genus of thalassophonean pliosaurid known from the Kimmeridgian and Tithonian stages of Europe and South America. Their diet would have included fish, cephalopods, and marine reptiles. This genus has contained many species in the past but recent reviews found only six to be valid, while the validity of two additional species awaits a petition to the ICZN. Pliosaurus currently consists of the type species P. brachydeirus, and also P. brachyspondylus, P. carpenteri, P. funkei, P. kevani, P. macromerus, P. rossicus and P. westburyensis, as well as the invalid P. portentificus. Most species of Pliosaurus are notable for their large body size, while the others, P. brachydeirus, P. brachyspondylus and P. portentificus, are known exclusively from immature individuals. Species of this genus are differentiated from other pliosaurids based on seven autapomorphies, including teeth that are triangular in cross section.
Brachauchenius is an extinct genus of pliosaurid that lived in North America during the Late Cretaceous.
Simolestes is an extinct pliosaurid genus that lived in the Middle to Late Jurassic. The type specimen, BMNH R. 3319 is an almost complete but crushed skeleton diagnostic to Simolestes vorax, dating back to the Callovian of the Oxford Clay formation, England. The genus is also known from the Callovian and Bajocian of France (S.keileni), and the Tithonian of India (S.indicus). The referral of these two species to Simolestes is dubious, however.
Archaeonectrus is an extinct genus of pliosaur from the Jurassic of what is now southeastern England. The type species is Archaeonectrusrostratus, first named by Sir Richard Owen in 1865, which was moved to its own genus by N.I. Novozhilov in 1964.
Predator X is a 2009 television special on the cable television channel History. The show documents the excavation of a giant pliosaur on an island in the Norwegian Svalbard archipelago. The special follows Dr. Jørn Hurum and a team of paleontologists from the University of Oslo as they excavate the site.
Pachycostasaurus is an extinct Pliosauroid from the Oxford Clay formation of Peterborough, England.
The "monster of Aramberri" is the denomination that was given to the fossil remains of a huge marine reptile, a giant carnivore belonging to the Pliosauroidea clade that was found in sedimens of the La Caja Formation in Aramberri, Nuevo León, Mexico by a student of the Facultad de Ciencias de la Tierra of the Universidad Autónoma de Nuevo León while conducting geological mapping in 1985.
This timeline of plesiosaur research is a chronologically ordered list of important fossil discoveries, controversies of interpretation, taxonomic revisions, and cultural portrayals of plesiosaurs, an order of marine reptiles that flourished during the Mesozoic Era. The first scientifically documented plesiosaur fossils were discovered during the early 19th century by Mary Anning. Plesiosaurs were actually discovered and described before dinosaurs. They were also among the first animals to be featured in artistic reconstructions of the ancient world, and therefore among the earliest prehistoric creatures to attract the attention of the lay public. Plesiosaurs were originally thought to be a kind of primitive transitional form between marine life and terrestrial reptiles. However, now plesiosaurs are recognized as highly derived marine reptiles descended from terrestrial ancestors.
Megacephalosaurus is an extinct genus of short-necked pliosaur that inhabited the Western Interior Seaway of North America about 94 to 93 million years ago during the Turonian stage of the Late Cretaceous, containing the single species M. eulerti. It is named after its large head, which is the largest of any plesiosaur in the continent and measures up to 1.75 meters (5.7 ft) in length. Megacephalosaurus was one of the largest marine reptiles of its time with an estimated length of 6–9 meters (20–30 ft). Its long snout and consistently sized teeth suggest that it preferred a diet on smaller-sized prey.
Judith Massare is a paleontologist specializing in Mesozoic marine reptile research. In 1987, Massare published an analysis of plesiosaur feeding habits. She concluded that the long-necked plesiosauroids ate soft prey. Liopleurodon and its relatives, on the other hand, had teeth resembling those of killer whales and probably ate larger, bonier prey. The next year, Massare analyzed Mesozoic marine reptile swimming abilities and found that long-necked plesiosaurs would have been significantly slower than pliosaurs due to excess drag incurred from their large round bodies.
Stenorhynchosaurus is an extinct genus of pliosaurid plesiosaurs which lived in South America during the Early Cretaceous. The type species and only known is Stenorhynchosaurus munozi.
Luskhan is an extinct genus of brachauchenine pliosaur from the Cretaceous of Russia. The type and only species is Luskhan itilensis, named by Valentin Fischer and colleagues in 2017 from a well-preserved and nearly complete skeleton. As an early-diverging brachauchenine, Luskhan consequently exhibits an intermediate combination of traits seen in more basal and more derived pliosaurs. However, Luskhan departs significantly from other pliosaurs in that it exhibits a lack of adaptations in its skull to feeding on large prey; its slender snout, small teeth, and short tooth rows instead indicate a skull adapted for feeding on small, soft prey. In these features, it is the pliosaur that approaches closest to the distantly-related piscivorous polycotylids, having convergently evolved these traits more than 10 million years apart.
Acostasaurus is an extinct genus of possibly Thalassophonean pliosaurid known from the Barremian of the Paja Formation, Colombia. The type specimen, UNDG R-1000, is known from a near complete skull, and postcranial elements including a complete hindlimb and various vertebrae. The specimen has an estimated size of around 4 to 5 metres long.
The Harvard Australian Expedition of 1931–1932 was a six-man venture sent by then Harvard Museum of Comparative Zoology (MCZ) director Thomas Barbour to Australia for the dual purpose of procuring specimens and studying native (living) wildlife in its natural habitat. The Expedition leader was Harvard Professor William Morton Wheeler, with the others being Dr. Philip Jackson Darlington, Jr., Dr. Glover Morrill Allen and his student Ralph Nicholson Ellis, medical officer Dr. Ira M. Dixon, and William E. Schevill . The Expedition was a success, with 341 mammal, 545 amphibian, and thousands of insect specimens returning to the United States., yet its most famous legacy and find was the accidental discovery of the world's most complete skeleton of the short-necked pliosaur Kronosaurus queenslandicus.
