The Scientific Explorations for Deep-Sea Fishes in Brazil: The Known Knowns, the Known Unknowns, and the Unknown Unknowns

The deep sea is the largest and one of the most extreme environments on Earth. It is estimated that 10–15% of all fish species are dwelling in the deep sea, most of which have unique morphological and physiological adaptations. Biological expeditions to sample the deep ocean off Brazil started with the British HMS Challenger Expedition (1872–1876), followed by a few fishery stations made by the German RV Ernst Haeckel (1966) and the North-American MIV Oregon II (1957–1975), the cruises of the French RVs Marion Dufresne (1987) and Thalassa (1999, 2000), the Brazilian RV Atlântico Sul (1996–1999), the FV Diadorim and FV Soloncy Moura (1996–2002), OSB Astro Garoupa (2003), and, more recently, the American RV Luke Thomas and Seward Johnson (2009, 2011), the French RV Antea (2015, 2017), and the Brazilian RV Alpha Crucis. A total of 712 species of deep-sea fishes were recorded, including five species of Myxini, six species of Holocephali, 81 species of Elasmobrachii, and 620 species of Actinopteri. As in other parts of the world, the Brazilian deep-sea ichthyofauna struggles under severe anthropogenic impacts caused by the commercial fishing, and the extraction of oil and gas. The deep ocean is a delicate environment and its recovery is considerably slower than an equivalent in shallow water habitat. Therefore, increasing the research efforts is needed to avoid that part of its diversity disappear without our accurate knowledge.https://nsuworks.nova.edu/occ_facbooks/1102/thumbnail.jp

Mesozoic dinosaurs from Brazil and their biogeographic implications

The record of dinosaur body-fossils in the Brazilian Mesozoic is restricted to the Triassic of Rio Grande do Sul and Cretaceous of various parts of the country. This includes 21 named species, two of which were regarded as nomina dubia, and 19 consensually assigned to Dinosauria. Additional eight supraspecific taxa have been identified based on fragmentary specimens and numerous dinosaur footprints known in Brazil. In fact, most Brazilian specimens related to dinosaurs are composed of isolated teeth and vertebrae. Despite the increase of fieldwork during the last decade, there are still no dinosaur body-fossils of Jurassic age and the evidence of ornithischians in Brazil is very limited. Dinosaur faunas from this country are generally correlated with those from other parts of Gondwana throughout the Mesozoic. During the Late Triassic, there is a close correspondence to Argentina and other south-Pangaea areas. Mid-Cretaceous faunas of northeastern Brazil resemble those of coeval deposits of North Africa and Argentina. Southern hemisphere spinosaurids are restricted to Africa and Brazil, whereas abelisaurids are still unknown in the Early Cretaceous of the latter. Late Cretaceous dinosaur assemblages of south-central Brazil are endemic only to genus or, more conspicuously, to species level, sharing closely related taxa with Argentina, Madagascar, Indo-Pakistan and, to a lesser degree, continental Africa.<br>O registro osteológico de dinossauros no Mesozóico brasileiro está restrito a rochas triássicas do Rio Grande do Sul e estratos cretáceos de várias partes do país. Isto inclui 21 espécies nominais, sendo duas referidas como nomina dubia, e 19 consensualmente classificadas como dinossauros. Oito táxons supraespecíficos adicionais baseados em material fragmentado e diversas pegadas são conhecidos no Brasil. De fato, a maior parte dos espécimes é composta de dentes isolados e vértebras. Apesar do aumento em trabalhos de campo na última década, não há exemplar esqueletal de dinossauro no Jurássico brasileiro, e é escassa a evidência de Ornithischia. Faunas dinossaurianas aqui registradas são em geral correlatas com aquelas da Pangéia durante o Mesozóico. No Triássico Superior, há uma correspondência próxima com a Argentina e outras regiões sul-gondwânicas. Faunas do Cretáceo médio do nordeste brasileiro são semelhantes às dos depósitos coevos do norte da África e Argentina. Registros de espinossaurídeos no hemisfério sul estão restritos à África e Brasil, enquanto abelissaurídeos não são conhecidos no Cretáceo Inferior deste último. Assembleias de dinossauros da região sul e central do Brasil são endêmicas apenas em nível de gênero e, mais conspicuamente, espécie, compartilhando táxons proximamente relacionados com assembleias da Argentina, Indo-Paquistão, e, num menor grau, África continental