Mosasaurs are an extinct group of large aquatic reptiles within the family Mosasauridae that lived during the Late Cretaceous. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. They belong to the order Squamata, which includes lizards and snakes.
The Halisaurinae are a subfamily of mosasaurs, a group of Late Cretaceous marine lizards. They were small to medium-sized, ranging from just under 3 meters in Eonatator sternbergi to as much as 8 or 9 meters in Pluridens serpentis. They tended to have relatively slender jaws and small, numerous teeth, suggesting a diet of small fish and other prey. Although the skeleton is primitive compared to other Mosasauridae in many respects, halisaurines had the distinctive hypocercal tail of other mosasaurids suggesting good swimming ability, and they persisted alongside other mosasaurs until the end of the Cretaceous. The earliest known remains of halisaurines occur in rocks of Santonian age and the subfamily persists until the latest Maastrichtian. Halisaurines are known from North and South America, Europe, Asia and Africa, indicating a more or less global distribution in the Late Cretaceous. Four genera are currently recognized: Eonatator, Halisaurus, Phosphorosaurus and Pluridens.
Phosphatherium escuillei Gheerbrant, Sudre et Cappetta 1996 is a basal proboscidean that lived in Africa during in the early Eocene, by 56-55 Ma. It is one of the earliest known proboscidean, together with Eritherium azzouzorum from the Selandian. It was found in phosphorites beds from the base of the Ypresian stage of the Ouled Abdoun Basin, which is best known for its exceptionally rich marine vertebrate fauna.
Phosphatodraco is a genus of azhdarchid pterosaur that lived during the Late Cretaceous of what is now Morocco. In 2000, a pterosaur specimen consisting of five cervical (neck) vertebrae was discovered in the Ouled Abdoun Phosphatic Basin. The specimen was made the holotype of the new genus and species Phosphatodraco mauritanicus in 2003; the genus name means "dragon from the phosphates", and the specific name refers to the region of Mauretania. Phosphatodraco was the first Late Cretaceous pterosaur known from North Africa, and the second pterosaur genus described from Morocco. It is one of the only known azhdarchids preserving a relatively complete neck, and was one of the last known pterosaurs. Additional cervical vertebrae have since been assigned to the genus, and it has been suggested that fossils of the pterosaur Tethydraco represent wing elements of Phosphatodraco.
Ocepesuchus is an extinct genus of gavialoid crocodilian, related to modern gharials. Ocepesuchus is the oldest known crocodilian of Africa, and is known only from a single species, O. eoafricanus. It lived in Morocco during the late Maastrichtian age of the Late Cretaceous.
Tethysaurus is an extinct genus of tethysaurine mosasauroid from the Early Turonian period. The only species is Tethysaurus nopcsai.
Zarafasaura is an extinct genus of elasmosaurid known from the Ouled Abdoun Basin of Morocco. As a relatively small elasmosaur, it would have measured around 3–4 metres (9.8–13.1 ft) long and weighed about 100 kilograms (220 lb).
Eremiasaurus 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.
Ocepeia is an extinct genus of afrotherian mammal that lived in present-day Morocco during the middle Paleocene epoch, approximately 60 million years ago. First named and described in 2001, the type species is O. daouiensis from the Selandian stage of Morocco's Ouled Abdoun Basin. A second, larger species, O. grandis, is known from the Thanetian, a slightly younger stage in the same area. In life, the two species are estimated to have weighed about 3.5 kg (7.7 lb) and 10 kg (22 lb), respectively, and are believed to have been specialized leaf-eaters. The fossil skulls of Ocepeia are the oldest known afrotherian skulls, and the best-known of any Paleocene mammal in Africa.
Chenanisaurus is a genus of predatory abelisaurid dinosaur, with a single known species C. barbaricus. It comes from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa. The animal is known from a holotype, consisting of a partial jaw bone, and several isolated teeth found in the same beds. Chenanisaurus is one of the largest members of the Abelisauridae, and one of the last, being a contemporary of the North American Tyrannosaurus. It would have been among the dinosaur species wiped out by the Chicxulub asteroid impact and the Cretaceous-Paleogene mass extinction that followed.
Tethydraco is a genus of pterodactyloid pterosaur that lived during the Late Cretaceous period of what is now the area of present Morocco, about 66 million years ago. Tethydraco was originally assigned to the family Pteranodontidae. Some researchers argued that subsequently described material suggests that it may have been an azhdarchid, and possibly synonymous with Phosphatodraco, though this has been disputed. The type and only species is T. regalis.
Ajnabia is a genus of lambeosaurine hadrosaur from the Late Cretaceous (Maastrichtian) of Morocco. It is the first definitive hadrosaur from Africa, and is thought to be related to European hadrosaurs like Arenysaurus. The discovery of Ajnabia came as a surprise to the paleontologists who found it, because Africa was isolated by water from the rest of the world during the Cretaceous, such that hadrosaurs were assumed to have been unable to reach the continent. Ajnabia is relatively small and similar in size to its contemporary relative Minqaria, which is estimated to have reached 3.5 metres (11 ft) in total body length. Assuming that the holotype represents an adult, Ajnabia would be one of the smallest if not the smallest known hadrosaurids.
Gavialimimus is an extinct genus of plioplatecarpine mosasaur from the Maastrichtian of Morocco and possibly Angola. It was a medium-sized mosasaur measuring around 6 metres (20 ft) in total body length.
Xenodens is a potentially dubious extinct genus of marine lizard belonging to the mosasaur family. It contains a single species, X. calminechari, which is known from Late Maastrichtian phosphate deposits in the Ouled Abdoun Basin, Morocco.
Thalassotitan is an extinct genus of large mosasaurs that lived during the late Maastrichtian of the Cretaceous period in what is now Morocco, around 67 to 66 million years ago. The only known species is T. atrox, described in 2022 from fossils discovered in the Ouled Abdoun Basin, initially identified as coming from other genera such as Mosasaurus or Prognathodon. Hypothetical Thalassotitan specimens may have been found in other corners of the world, although researchers also note the possibility that they come from distinct, related taxa. It is considered to be close to the genera Prognathodon and Gnathomortis, together forming the tribe Prognathodontini. The prognathodontines are separated from other mosasaurs based on their massive jaws and robust teeth.
Stelladens is an extinct genus of mosasaurine mosasaurs from the Late Cretaceous Ouled Abdoun Basin of Morocco. The genus contains a single species, S. mysteriosus. It was a medium-sized mosasaur, measuring about 5 metres (16 ft) long.
Minqaria is a genus of arenysaurinin lambeosaurine hadrosaur from the Late Cretaceous (Maastrichtian) Ouled Abdoun Basin of Morocco. The genus contains a single species, M. bata, known from a partial skull.
Khinjaria is an extinct genus of plioplatecarpine mosasaurid from the Late Cretaceous Ouled Abdoun Basin of Morocco. The genus contains a single species, K. acuta, known from a partial skull and vertebra. Khinjaria was likely an apex predator in its environment, as its large body size, blade-like teeth, and unusual skull morphology would have allowed it to attack large prey animals.
Grand Daoui is a quarry in the Ouled Abdoun Basin of Morocco known for its fossils. It is the discovery place of Phosphatherium escuilliei, the earliest known proboscidean. It was the location for several field parties between 1997 and 2001, which allowed survey of the geological and paleontological context of Phosphatherium localities. It is also rich in marine vertebrae fossils. All Phosphatherium remains to date have been found in the quarry. The discovery of fossils there has aided in the study of early African placental fauna. The marine snake Palaeophis maghrebianus is also known from the locality, as well as the primitive gavialoid Argochampsa krebsi.
Morocco 
