Although occurrences of marine reptiles have been previously reported from Angola, with the exception of two Turonian taxa, these reports were based largely on isolated teeth. Fieldwork in 2005 and 2006 yielded well-preserved remains of marine reptiles including plesiosaurs, turtles, and mosasaurs. The mosasaurs discussed here were recovered from two field areas: Turonian sediments at Iembe along the north coast and Maastrichtian sediments at Bentiaba on the south coast. The Turonian section near Iembe produced at least two new specimens of Angolasaurus bocagei and one fragmentary specimen of Tylosaurus iembeensis. One of the Angolasaurus specimens is represented by a well preserved, complete and articulated skull and partial postcrania, including portions of the forelimbs and pectoral girdle. The preservation of material from the Bentiaba locality is remarkable due to the grain support of the entombing sandstone, which preserves fine anatomical details with little apparent crushing, and in the number of articulated, semi-articulated, and associated skeletons. Identifications from the field and preliminary preparation show the Bentiaba mosasaur fauna is represented by at least five genera including Mosasaurus, Prognathodon, Globidens, Plioplatecarpus and Halisaurus. Collectively, these new specimens greatly expand our knowledge of the anatomy and systematics of Angolan mosasaurs.

Recent fieldwork in the Namibe province in southern Angola yielded cranial and postcranial elements of at least two individuals of the rare and enigmatic mosasaur Halisaurus from a single small excavation. The genus Halisaurus is unique in retaining a primitive configuration of the temporal arcade, specifically a broad, vertically oriented contact between the parietal and the supratemporal. The supratemporal is broadly sutured to the opisthotic and prootic, unlike the condition in varanoids in which the simple lunate element lies between the parietal ramus and the squamosal and does not form a sutural contact with the opisthotic or prootic, but as in other halisaurines retains a plesiomorphic, vertically oriented contact with the parietal rami. The squamosal is lightly built and broadly arched as in Varanus. Comparison with known halisaurines indicates the new material is referable to the species Halisaurus arambourgi.
The locality that yielded the new specimens has also yielded a large number of isolated teeth, bones, articulated, and associated skeletons of Mosasaurus, Prognathodon, Globidens, and Plioplatecarpus, which with Halisaurus comprise a mosasaur assemblage most similar to that reported from the Maastrichtian of Morocco.