73 research outputs found
Critical review of radiopharmaceutical-drug interactions, unexpected new age for a Tupiguarani settlement, and the h-index in the Brazilian Academy of Sciences
First record of a clupeomorph fish in the Neuquén Group (Portezuelo Formation), Upper Cretaceous of Patagonia, Argentina
AbstractA new genus and species of clupeomorph fish, Leufuichthys minimus, is described from the fluvial deposits of the Portezuelo Formation, Upper Cretaceous (Turonian–Coniacian) of the Neuquén Group, Patagonia, Argentina. It is a small-sized fish with an estimated body length up to 46mm. Among other characters, the new species shows the following: abdominal scutes; abdomen moderately convex; anal fin elongate-based; three uroneurals; two epurals; caudal fin bearing very elongate rays; and cycloid scales. Leufuichthys minimus gen. et sp. nov. shows a greater similarity with Kwangoclupea dartevellei, a clupeomorph described from a marine Cenomanian deposit of the Democratic Republic of Congo (Africa), mainly due to the presence of an elongate-based anal fin, bearing more than 20 fin-rays, differing from it by the presence of a not hypertrophied abdomen. As far as known, L. minimus gen. et sp. nov. is the first clupeomorph described in the Upper Cretaceous of Patagonia and represents one fortuitous preservation of an articulated fish in fluvial deposits
A new species of Comahuesuchus Bonaparte, 1991 (Crocodyliformes: Notosuchia) from the Upper Cretaceous of Neuquén, Lake Barreales, Patagonia, Argentina
Abstract Notosuchian crocodyliforms were major components of the South American Cretaceous biota and, for over 125 years, paleontological fieldwork in this continent recovered several well-preserved fossils of these animals. They are largely recognized for terrestrial life and specialized feeding habits, frequently presenting bizarre taxa such as Comahuesuchus. A new species, Comahuesuchus bonapartei n. sp. (MUCPv 597; cast MN), is described from geological strata of Sierra Barrosa Formation (Upper Turonian) and Portezuelo Formation (Lower Coniacian) of Lake Barreales, Patagonia, Argentina. The new fossil comprises a right dentary bone that shares important and unique anatomical features with specimens of Comahuesuchus brachybuccalis, such as the presence of a well-marked shelf on the lateral surface of the bone; a flat, low, and wide mandibular symphysis; an enlarged, labiolingually compressed caniniform tooth at caudal position in the dentary; the presence of serrated mesial and distal carinae in the caniniform with a faceted labial surface, and the absence or extremely reduction in number of the postcaniniform dentition. C. bonapartei differs from C. brachybuccalis in having individual dentary alveoli, rather a dentition set in groove. Phylogenetic analyses support a sister-relationship between both species, which are well nested within notosuchians
New information on molecular features of the dengue virus type 3, panorama of the amphibian research in Brazil, and a new extinct Cretaceous angiosperm
Phytogeographic patterns of the Atlantic Forest in the Rio Doce River Basin, the dart versus arrow debate, and quorum sensing in bacteria
Sugarcane and cancer, scientometrics, and phytoplankton dynamics of a beach in the Amazon
Heavy metals partitioning in the Rodrigo de Freitas lagoon; larvicidal potential of a new essential oil against Aedes aegypti; and the socioeconomic impact of tourism due to wild dolphins provisioning
First evidence of the Ediacaran fauna in Northeastern Brazil, an albino dolphin, and trophic groups of a bird community in Alagoas
New parasite in a coprolite of 240 million years, biogeography of fossil coelacanths, and the influence of air pollutants in a coastal area of northeastern Brazil
Niche overlap analysis of a lizard assemblage from the Atlantic Rainforest, evaluation of arsenic toxicity in cladocerans, and molecular biology of mycoplasmas
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