Recent advances in the comprehension of the biogeography of Cretaceous European eusuchians

Within the last two decades, a growing interest has emerged with the aim of understanding the structure of the paleocommunities from Cretaceous continental deposits of Europe. Conspicuous research efforts have concentrated on outcrops from Northern Spain, Southern France, Italy, and Romania. Of special relevance are the researches in Romanian outcrops because they considerably extend the sampling eastward, providing a wide geographical scope in faunal comparisons across the Cretaceous European archipelago. Excavations have yielded previously unknown vertebrates, including members of Crocodilia. Most Late Cretaceous eusuchians reported so far have been from North America with a few European exceptions: Hylaeochampsa vectiana Owen, Bernissartia fagesii Dollo, Allodaposuchus precedens Nopcsa from Valioara, Romania, and ‘Crocodilus’ affuvelensis Matheron. Here, the fossil record of European eusuchians is reviewed and peculiarities of the emergence of Eusuchia in Europe are discussed in light of the faunal turnover that occurred between the Early and Late Cretaceous. Additionally to biomechanical novelties tied to evolutionary landmarks marking the transition between advanced neosuchians to eusuchians, other possible factors are put forward and discussed. As such, climatic conditions and paleogeographic settings may have permitted faunal exchanges between North America and Europe, as suggested by the study of other vertebrates. Further, the present review provides a basis for a comparison with other Laurasian and Gondwanan faunas of the Cretaceous.