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The jigsaw-puzzle fit of South America and Africa is an icon of plate tectonics and continental drift. Fieldwork in Angola since 2002 allows the correlation of onshore outcrops and offshore geophysical and wellcore data in the context of rift, sag, salt, and post-salt drift phases of the opening of the central South Atlantic. These outcrops, ranging in age from >130 Ma to <71 Ma, record Early Cretaceous outpouring of the Etendeka–Paraná Large Igneous Province (Bero Volcanic Complex) and rifting, followed by continental carbonate and siliciclastic deposition (Tumbalunda Formation) during the sagging of the nascent central South Atlantic basin. By the Aptian, evaporation of sea water resulted in thick salt deposits (Bambata Formation), terminated by seafloor spreading. The Equatorial Atlantic Gateway began opening by the early Late Cretaceous (100 Ma) and allowed flow of currents between the North and South Atlantic, creating environmental conditions that heralded the introduction of marine reptiles. These dramatic outcrops are a unique element of geoheritage because they arguably comprise the most complete terrestrially exposed geological record of the puzzle-like icon of continental drift.

The Upper Maastrichtian of Morocco has produced a remarkably diverse fauna of mosasaurids, the most diverse known for any time or place. As apex predators, Mosasauridae provide a picture of the marine ecosystem just before the end-Cretaceous mass extinction. Here we describe a bizarre new plioplatecarpine mosasaurid, Khinjaria acuta, characterized by enlarged, dagger-like anterior teeth, short, robust jaws, and posterior elongation of the skull. Khinjaria is related to Goronyosaurus nigeriensis from Nigeria and Niger, and Gavialimimus almaghribensis from Morocco. These species form a distinct clade of specialized mosasaurids so far unknown outside of Africa. Mosasaurids show high endemism in the Maastrichtian, with different lineages occurring in different regions, implying that mosasaurid diversity is underestimated because of limited geographic sampling. The large size, robust jaws, akinetic skull, and bladelike teeth of Khinjaria suggest it was an apex predator, but the unusual skull and jaw differ from those of contemporary predators like Hainosaurus, Thalassotitan, and Mosasaurus, suggesting a distinct feeding strategy. Mosasaurids became increasingly specialized in the latest Cretaceous, repeatedly evolving to occupy the apex predator niche, suggesting a diverse marine ecosystem persisted up to the K/Pg boundary. Late Cretaceous marine ecosystems differ from modern marine ecosystems in the high diversity of large predators.

In this contribution we report a spectacularly well-preserved, semi-articulated specimen of Prognathodon kianda containing three partial mosasaurs in its stomach region. The discovery is from the lower Maastrichtian (~71.5Ma) “Bench 19 Bonebed” at Bentiaba, Angola. Each of the three mosasaurs found in the gut region is a unique taxon, one being the first documented occurrence of cannibalism in mosasaurs, and another representing a new mosasaurine genus and species, Bentiabasaurus jacobsi gen. et sp. nov., a taxon closely related to Mosasaurus. Trophic interactions at the “Bench 19 Bonebed” locality appear to be controlled in part by relative size of the predator and the prey, all prey taxa falling between 43 and 57% of the predator’s body length. Prey items are all dismembered to some degree and individual parcels approach the estimated maximum sizes that can pass the gullet. Tooth and bone modification, and other aspects of prey processing are discussed. Though the sample is small, the observed range of modalities suggests prey processing, digestive biology, and methods of elimination in mosasaurs was diverse.

Here, we describe the first pterosaur remains from Angola, an assemblage of fourteen bones from the Lower Maastrichtian marine deposits of Bentiaba, Namibe Province. One new species is introduced, Epapatelo otyikokolo, gen. et sp. nov., which comprises an articulated partial left humerus and ulna as well as an articulated left ulna and radius (from a second individual). Phylogenetic analysis confirms a non-nyctosaurid pteranodontian attribution for this new taxon and supports a new apomorphy-based clade, Aponyctosauria, which is here defined. Late Cretaceous pteranodontians are rare in Sub-Saharan Africa and throughout the Southern Hemisphere. Preliminary histological analysis also reveals a likely sub-adult age for one of the specimens. This fossil assemblage provides a first glimpse of Angolan pterosaur paleobiodiversity providing further insight into the Gondwanan ecosystems of the Upper Cretaceous.

Low concentrations of the structural protein collagen have recently been reported in dinosaur fossils based primarily on mass spectrometric analyses of whole bone extracts. However, direct spectroscopic characterization of isolated fibrous bone tissues, a crucial test of hypotheses of biomolecular preservation over deep time, has not been performed. Here, we demonstrate that endogenous proteinaceous molecules are retained in a humerus from a Late Cretaceous mosasaur (an extinct giant marine lizard). In situ immunofluorescence of demineralized bone extracts shows reactivity to antibodies raised against type I collagen, and amino acid analyses of soluble proteins extracted from the bone exhibit a composition indicative of structural proteins or their breakdown products. These data are corroborated by synchrotron radiation-based infrared microspectroscopic studies demonstrating that amino acid containing matter is located in bone matrix fibrils that express imprints of the characteristic 67 nm D-periodicity typical of collagen. Moreover, the fibrils differ significantly in spectral signature from those of potential modern bacterial contaminants, such as biofilms and collagen-like proteins. Thus, the preservation of primary soft tissues and biomolecules is not limited to large-sized bones buried in fluvial sandstone environments, but also occurs in relatively small-sized skeletal elements deposited in marine sediments.