RussellosaurusRussellosaurus is an extinct genus of tethysaurine mosasauroid from the Late Cretaceous of North America. The genus was described from a skull discovered in an exposure of the Arcadia Park Shale (lower Middle Turonian) at Cedar Hill, Dallas County in the south-central part of the DFW Metroplex in Texas, United States. The skull (SMU 73056, Shuler Museum of Paleontology, Southern Methodist University) was found in 1992 by a member of the Dallas Paleontological Society, who then donated to the museum.
Leatherback sea turtleThe leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle, leathery turtle or simply the luth, is the largest of all living turtles and the heaviest non-crocodilian reptile, reaching lengths of up to and weights of . It is the only living species in the genus Dermochelys and family Dermochelyidae. It can easily be differentiated from other modern sea turtles by its lack of a bony shell; instead, its carapace is covered by oily flesh and flexible, leather-like skin, for which it is named.
ViviparityAmong animals, viviparity is development of the embryo inside the body of the mother. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the mother. The term 'viviparity' and its adjective form 'viviparous' derive from the Latin vivus meaning "living" and pario meaning "give birth to". Five modes of reproduction have been differentiated in animals based on relations between zygote and parents.
PlioplatecarpusPlioplatecarpus is a genus of mosasaur lizard. Like all mosasaurs, it lived in the late Cretaceous period, about 73-68 million years ago. Plioplatecarpus has been found in many locations around the world (most mosasaurs were fairly widespread). Plioplatecarpus has been found in the Pierre Shale of Kansas, Demopolis Chalk of Alabama, and also in Mississippi, North Dakota, South Dakota, Canada, Sweden, The Netherlands. It was first found in Europe by paleontologist Louis Dollo (P. marshi), in 1882.
EremiasaurusEremiasaurus ("desert lizard") is a genus of mosasaurs, an extinct group of marine reptiles. It lived during the Maastrichtian stage of the Late Cretaceous in what is now North Africa. Only one species is known, E. heterodontus, described in 2012 from two remarkably complete fossil specimens discovered in the Ouled Abdoun Basin, Morocco. This site is known to have delivered a significant number of other related mosasaurs. Eremiasaurus is a medium-sized representative for mosasaurs, estimated to be around long based on observations made on the syntype specimens.
SelmasaurusSelmasaurus is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Plioplatecarpinae subfamily alongside genera like Angolasaurus and Platecarpus. Two species are known, S. russelli and S. johnsoni; both are exclusively known from Santonian deposits in the United States. Selmasaurus is unique among the mosasaurs in that its skull is unusually akinetic, meaning that it is incapable of widening to swallow larger prey.
CountershadingCountershading, or Thayer's law, is a method of camouflage in which an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptiles, birds, fish, and insects, both in predators and in prey. When light falls from above on a uniformly coloured three-dimensional object such as a sphere, it makes the upper side appear lighter and the underside darker, grading from one to the other.
HalisaurusHalisaurus is an extinct genus of marine reptile belonging to the mosasaur family. The holotype, consisting of an angular and a basicranium fragment discovered near Hornerstown, New Jersey, already revealed a relatively unique combination of features and prompted a new genus to be described. It was named by Othniel Charles Marsh in 1869 and means "ocean lizard". It was renamed by Marsh to Baptosaurus in 1870, since he believed the name to already be preoccupied by the fish Halosaurus.
EctenosaurusEctenosaurus is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Plioplatecarpinae subfamily alongside genera like Angolasaurus and Platecarpus. Ectenosaurus is known from the Santonian and Campanian of Kansas, Alabama, and Texas. The generic name means "drawn-out lizard", from Greek ectenes ("drawn-out") and Greek sauros ("lizard") referencing the elongated muzzle. With the preserved skull about long and the dorsal vertebrae about , Ectenosaurus is estimated to have reached in length and in body mass.
MosasauriniMosasaurini is a extinct tribe of mosasaurine mosasaurs who lived during the Late Cretaceous and whose fossils have been found in North America, South America, Europe, Africa and Oceania, with questionable occurrences in Asia. They are highly derived mosasaurs, containing genera like Plotosaurus, having unique adaptations to fast swimming speeds, or Mosasaurus, which is among the largest known marine reptiles. The Mosasaurini form a clade of derived mosasaurine.
