The extinct group of the Pycnodontiformes is one of the most characteristic components of the Mesozoic and early Cenozoic fish faunas. These ray-finned fishes, which underwent an explosive morphological diversification during the Late Cretaceous, are generally regarded as typical shell-crushers. Here we report unusual cutting-type dentitions from the Paleogene of Morocco which are assigned to a new genus of highly specialized pycnodont fish. This peculiar taxon represents the last member of a new, previously undetected 40-million-year lineage (Serrasalmimidae fam. nov., including two other new genera and Polygyrodus White, 1927) ranging back to the early Late Cretaceous and leading to exclusively carnivorous predatory forms, unique and unexpected among pycnodonts. Our discovery indicates that latest Cretaceous–earliest Paleogene pycnodonts occupied more diverse trophic niches than previously thought, taking advantage of the apparition of new prey types in the changing marine ecosystems of this time interval. The evolutionary sequence of trophic specialization characterizing this new group of pycnodontiforms is strikingly similar to that observed within serrasalmid characiforms, from seed- and fruit-eating pacus to flesh-eating piranhas.

Late Eocene deposits of the Samlat Formation, south of Ad-Dakhla city, southwestern Morocco, have yielded a mixed marine and terrestrial vertebrate fauna. Abundant and diversified chondrichthyans and archaeocete whales have been found, as well as the remains of sirenians and proboscideans. Here we describe the rest of this fossil assemblage which includes actinopterygians, turtles, palaeophiid snakes, crocodiles and pelagornithid seabirds. Actinopterygians are represented by at least two large-sized taxa, a scombroid probably close to the extantAcanthocybiumor to the EoceneAramichthys, and a siluriform related to the Ariidae. Turtles include at least four species represented by shell fragments. This mixed coastal and continental turtle fauna includes one littoral species of Podocnemididae, one or two deep-sea species of Dermochelyidae and one deep-sea species of Cheloniidae. Another turtle species is assigned to the terrestrial Testudinidae. Fragmentary crocodilian remains indicate the presence of undetermined eusuchians tentatively referred to Gavialidae and/or to Crocodylidae. Snake vertebrae are tentatively attributed to the genusPterosphenus(Palaeophiidae) pending the discovery of new material. Avian remains belong to a large pseudo-toothed bird (Pelagornithidae). Pseudo-tooth morphology resembles that of the late Oligocene – Neogene genusPelagornis. Additional bird remains are needed for a more precise taxonomic assignment. The fossil assemblage and palaeoenvironment of the upper Eocene deposits of the Samlat Formation appear closely related to those of the upper Eocene – lower Oligocene deposits of the Fayum (Egypt). The initial overview of this fauna provides an important contribution to the study of vertebrate evolution in North Africa near the Eocene–Oligocene transition.

-A previously undocumented marine vertebrate fauna comprising ichthyosaur, plesiosaur, marine crocodilian and fish remains from the Toarcian-Aalenian succession at Lafarge quarry, southern Beaujolais (Rhône, France) is described on the basis of both historical collections and new discoveries. The taxonomic composition of the Lafarge quarry marine vertebrate assemblage highlights its cosmopolitan nature and strong relationships with taxa known from elsewhere in Europe. Several groups are recorded for the first time in the Toarcian-Aalenian succession of France, implying new palaeobiogeographic interpretations and prompting discussion of marine amniote diversity during this interval.

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ABSTRACT-A new double-armored member of the Ellimmichthyiformes (Clupeomorpha, Teleostei) is described from the Cenomanian (Upper Cretaceous) of Ein Yabrud, near Ramallah, Middle East. The anatomical description of Rhombichthys intoccabilis, gen. et sp. nov., is based on 13 subcomplete or incomplete acid-prepared specimens. This taxon shows several remarkable characters such as an important dorsoventral elongation of the lateral wings of the ventral scutes that give an apex-shaped ventral profile in the biggest specimens. Some dorsal fin rays are very extended and branched, and the dorsal fin extends along the major part of the dorsal margin of the body. Rhombichthys intoccabilis, gen. et sp. nov., shares the synapormorphies of the family Paraclupeidae and the subfamily Paraclupeinae. It appears closely related to the genera Triplomystus and Ez kutuberez i, mainly in the basis of the shape of dorsal and ventral scutes and the absence of a hypural diastema.

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The Eocene-Oligocene transition was a period of high faunal and floral turnover, often correlated with climatic deterioration. Crocodyliforms are climate sensitive, and they have been often used for reconstruction of paleoclimates. The description of crocodylian material from the Bartonian of Aaiun-Tarfaya Basin (Morocco) allows the recognition of at least two longirostrine crocodylians, including a gavialoid. This identification is important, because the migration of gavialoids to South America probably occurred during the late Eocene. Close relationships between late Eocene-early Oligocene Eogavialis africanum from Egypt, Argochampsa krebsi from the Paleocene of Morocco, and the South American gavialoid clade suggests that Morocco could have had a particular place in the gavialoid dispersal route to South America. The resemblance between Moroccan material described herein and E. africanum is thus important in this context. Analysis of the distribution of longirostrine crocodylians in the Peri-Tethys area through the Eocene-Oligocene shows a strong difference in the evolution of the distribution between longirostrine crocodylians and Diplocynodon. Whereas the freshwater Diplocynodon has a continuous distribution in western Europe, the mainly marine longirostrine crocodylians have a northern maximal expansion that moves southward during the middle Eocene, being restricted to North Africa during late Eocene-early Oligocene. European freshwater Asiatosuchus-like taxa also disappear during the late Eocene. Climatic deterioration, helped by sea level oscillations, may have strongly impacted the diversity and latitudinal distribution of the crocodylians, but we highlight a possible differential tolerance in range of climatic conditions between crocodylians. This could help to refine the use of crocodylians as paleoclimatic proxies.

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