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We provide a thorough re-evaluation of the taxonomic diversity, phylogenetic relationships, and historical biogeography of the lambeosaurine hadrosaurids from the European Archipelago. Previously published occurrences of European Lambeosaurinae are reviewed and new specimens collected from upper Maastrichtian strata of the south-central Pyrenees are described. No support is found for the recognition of European saurolophines in the available hadrosaurid materials recovered so far from this area. A new genus and species of basal lambeosaurine, Canardia garonnensis, is described on the basis of cranial and appendicular elements collected from upper Maastrichtian strata of southern France. C. garonnensis differs from all other hadrosaurids, except Aralosaurus tuberiferus, in having maxilla with prominent subrectangular rostrodorsal flange; it differs from A. tuberiferus in a few maxillary and prefrontal characters. Together with A. tuberiferus, C. garonnensis integrates the newly recognized tribe Aralosaurini. Inference of lambeosaurine interrelationships via maximum parsimony analysis indicates that the other three known European lambeosaurines are representatives of two additional subclades (tribes) of these hadrosaurids: Tsintaosaurini (Pararhabdodon isonensis) and Lambeosaurini (the Arenysaurus ardevoli-Blasisaurus canudoi clade). The tribes Aralosaurini, Tsintaosaurini, Lambeosaurini, and Parasaurolophini are formally defined and diagnosed for the first time. Three event-based quantitative methods of ancestral range reconstruction were implemented to infer the historical biogeography of European lambeosaurines: Dispersal-Vicariance Analysis, Bayesian Binary MCMC, and Dispersal-Extinction-Cladogenesis. The results of these analyses, coupled with the absence of pre-Maastrichtian lambeosaurines in the Mesozoic vertebrate fossil record of Europe, favor the hypothesis that aralosaurins and tsintaosaurins were Asian immigrants that reached the Ibero-Armorican island via dispersal events sometime during the Maastrichtian. Less conclusive is the biogeographical history of European lambeosaurins; several scenarios, occurring sometime during the Maastrichtian, are possible, from vicariance leading to the splitting of Asian or North American from European ranges to a dispersal event from North America to the European Archipelago.

A comprehensive review and study of the rich dinosaur track record of the Tremp Formation in the southern Pyrenees of Spain (Southwestern Europe) shows a unique succession of footprint localities prior to the end-Cretaceous mass extinction event. A description of some 30 new tracksites and data on sedimentary environments, track occurrence and preservation, ichnology and chronostratigraphy are provided. These new track localities represent various facies types within a diverse set of fluvial environments. The footprint discoveries mostly represent hadrosaurian and, less abundantly, to sauropod dinosaurs. The hadrosaur tracks are significantly smaller in size than, but morphologically similar to, those of North America and Asia and are attributable to the ichnogenus Hadrosauropodus. The track succession, with more than 40 distinct track levels, indicates that hadrosaur footprints in the Ibero-Armorican region occur predominantly in the late Maaastrichtian (at least above the early Maastrichtian–late Maastrichtian boundary). The highest abundance is found noticeably found in the late Maastrichtian, with tracks occurring in the C29r magnetochron, within about the latest 300,000 years of the Cretaceous.