Laopteryx Laopteryx Laopteryx is the name assigned to a pterosaur (flying reptile) from the Upper Jurassic Morrison Formation of Wyoming, United States; it was originally thought to be a bird. The genus was named in 1881 by Othniel Charles Marsh. The generic name is derived from Greek "laas", "stone", and "pteryx", "wing". The full species name given by Marsh was "Laopteryx priscum"; the specific name meaning "of venerable age" in Latin. However, Marsh incorrectly used the neuter form, while "pteryx" is feminine in Greek. (See grammatical gender.) This was in the 19th century emended to an, also incorrect, masculine "priscus" and
South Polar region of the Cretaceous notably the rhomaleosaurids and "Leptocleidus", which died out in the Early Cretaceous, indicating the polar freshwater systems may have been a refuge for the pliosaurs of the Cretaceous. In contrast to modern marine reptiles, these South Polar plesiosaurs probably had a better tolerance of colder waters. Early to Middle Cretaceous marine reptile remains of South Australia include five families of plesiosaurs–Cryptoclididae, Elasmosauridae, Polycotylidae, Rhomaleosauridae, and Pliosauridae–and the ichthyosaur family Ophthalmosauridae. The discovery of several juvenile plesiosaur remains suggest they used the nutrient-rich waters of the coast as sheltered calving grounds, the cold deterring predators such as sharks. Most of the