The Lontras Shale (Permian, Paraná Basin) and its Fossils: Discovery, Taxonomic Identification and Present Knowledge

The Shaler Memorial Fund created in 1907 by students and admirers of the geologist Nathaniel Southgate Shaler, professor from Harvard University, allowed in its first contribution to fostering research, the organization of an expedition to the South and Southeast of Brazil. The expedition had the purpose to confirm Nathaniel`s ideas about the existence of glacial layers older then the Pleistocene. Led by the North American geologist Jay Backus Woodworthy and counting with participation of the Brazilian geologist Euzébio de Oliveira, the expedition not only proved the presence of glacial evidence but also discovered an intercalated fossiliferous marine shale, later known as Lontras Shale, Itararé Group. The fossils, initially studied by the American paleontologist Rudolf Ruedemann and by Euzébio de Oliveira, had its studies intensified from the 1980s with the identification of new outcrops and due the new data of the geological evolution of the carboniferous and permian sedimentary sucessions of the Paraná Basin. Economic disputes and discussion about the preservation of Lontras Shale outcrops, besides the discovered of new site namely as CAMPÁLEO, have reactivated the scientific interest about this unit and its paleontological content, increasing its studies. Poorly known by the Brazilian academic community, the historical context of the Lontras Shale is here reported, highlighting the importance of the Shale Memorial Fund as responsible for the geological and paleontological discoveries that have followed, for more than a century.