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In Argentina, some of the most important dinosaur tracksites are found on the west coast of the Ezequiel Ramos Mexía reservoir, in the Neuquén province. In the last 30 years, more than 100 km of coastline have yielded hundreds of dinosaur tracks. The tracks are part of the Albian?-lower Cenomanian Candeleros Formation, Neuquén Group. An extensive study and review of the dinosaur tracks described in the past 30 years is reinterpreted and revised. Candeleroichnus canalei ichnogen. nov. ichnosp. nov. is described. A neotype is chosen for Deferrariischnium mapuchensis Calvo, 1991 and an emended diagnosis improves the ichnospecies. In addition, new information of the trackway diagnosis of Picunichnus benedettoi Calvo, 1991, such as length of pace and pace angle is given. We analyze all the dinosaur sites discovered until now and we identify all described ichnoforms such as Sousaichnium monettae, Limayichnus major, Abelichnus astigarrae and Sauropodichnus giganteus. We include unpublished figures, photos and tables of the ichnotypes. [ABSTRACT FROM AUTHOR]

Abstract: We describe a new titanosaurian braincase (MML-194), from the Upper Cretaceous (middle Campanian–lower Maastrichtian) of Río Negro Province, Argentina. Among titanosaurs, this specimen resembles Bonatitan reigi, more than any other member of the clade; the similarity is based on the supraoccipital protuberance bearing a median groove (also present in Saltasaurus and Rapetosaurus), the prominent basal tubera, the exit for the nerve VII located on the prootic crest, the occipital condyle and the foramen magnum almost of the same width. This material allows to observe some internal structures that are not appreciable in other titanosaurs, such as the pituitary cavity, the dorsum sellae and the foramen for the passage of the internal carotids, among other characters. The specimen MML-194 and Bonatitan were exhumed of same geological unit, the Allen Formation, from which have also been collected fossil eggs assignable to sauropods (megalooliths), for what is not unlikely that some of these taxa has been responsible of the laying of those eggs. [Copyright &y& Elsevier]

Abstract: An incomplete skeleton from Puesto Morales (Neuquén Province, Argentina) is described as a new species of sauropod, Zapalasaurus bonapartei. The unit that yielded the holotype of this dinosaur is the Piedra Parada Member of the La Amarga Formation, whose age is regarded as Barremian-lower Aptian. Several characters are interpreted as autapomorphies of Zapalasaurus bonapartei: cervical vertebrae with a lamina uniting the prezygapophysis and the zygapophyseal portion of the postzygodiapophyseal lamina, cervical vertebrae with the diapophyseal portion of the postzygodiapophyseal lamina reduced, cervical vertebrae with poorly developed spinoprezygapophyseal laminae, mid and posterior caudal vertebrae with anteroposteriorly elongated neural spines, whose anterodorsal corners are higher than their posterodorsal ones, and caudal centrum length doubles over first 20 vertebrae. Zapalasaurus bonapartei is considered as the sister group of the other diplodocoids (excluding Haplocanthosaurus). Diplodocoids were abundant in the Early Cretaceous, becoming extinct by the early Late Cretaceous. The record of Zapalasaurus bonapartei shows that, at least in the Neuquina Basin, basal diplodocoids were more diverse than previously thought. [Copyright &y& Elsevier]