A dearth of Mesozoic-aged, three-dimensional fossils hinders understanding of the origin of the distinctive skull and brain of modern (crown) birds. Here we report Navaornis hestiae gen. et sp.
View Article and Find Full Text PDFFossil microeukaryotes are key elements for understanding ancient ecosystems at microscopic level and improving the knowledge on the diversification of microbial life as a whole. We describe Palaeohypothrix bahiensis gen. et sp.
View Article and Find Full Text PDFWe describe the basal mesoeucrocodylian Burkesuchus mallingrandensis nov. gen. et sp.
View Article and Find Full Text PDFThe Solimões Formation (Eocene-Pliocene) is a well-known geological unit due to the great diversity of crocodylian species. Here we describe a new species of Melanosuchus, M. latrubessei sp.
View Article and Find Full Text PDFThe fossil record of birds in the Mesozoic of Gondwana is mostly based on isolated and often poorly preserved specimens, none of which has preserved details on feather anatomy. We provide the description of a fossil bird represented by a skeleton with feathers from the Early Cretaceous of Gondwana (NE Brazil). The specimen sheds light on the homology and 3D structure of the rachis-dominated feathers, previously known from two-dimensional slabs.
View Article and Find Full Text PDFSphagesaurus montealtensis is a sphagesaurid whose original description was based on a comparison with Sphagesaurus huenei, the only species of the clade described to that date. Better preparation of the holotype and the discovery of a new specimen have allowed the review of some characteristics and the identification of several synapomorphies of S. montealtensis with the genus Caipirasuchus: presence of antorbital fenestra; external nares bordered only by the premaxillae; premaxilla with four teeth and one diastema (between the 3rd-4th teeth); one diastema between the 4th premaxillary tooth and the 1" maxillary tooth; dentary with ten teeth and two diastemata (between the 4th-5th and 5th-6th teeth); nasal with a groove parallel to the suture with the frontal bone; nasal long, with an acute anterior margin touching anterolaterally the premaxilla, jugal is a straight bar in the lateral view; frontal is longer than wide; a dorsoventrally expanded and vertically oriented quadrate with a groove separating the medial and lateral condyles; the frontal has a discrete sagittal crest; dentary with six posterior sphagesauriform teeth and four anterior conical teeth, the first three are the smallest of the series and the fourth is slightly laterally compressed.
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