74 resultados para Rio Tapajós - PA
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
A new species of thorny catfish (family Doradidae) is described as a member of genus Leptodoras Boulenger by having a modified oral hood and first gill arch with enlarged accessory lamellae extending well onto medial face of gill filaments. The new species is distinguished by three characteristics unique within Leptodoras: gas bladder moderately sized (not reduced) with simple walls (diverticula absent), and paired bony capsules on anteriormost vertebrae reduced to paired cup-like laminar ossifications separated by triangular septum. The new species was discovered from material recently collected in the Tapajós basin at Serra do Cachimbo and in the headwaters of rio Xingu. The species description is supplemented by a detailed osteological description, discussion on its placement among congeners, and a re-evaluation of the diagnosis of Leptodoras and its relationships with sister taxon Anduzedoras oxyrhynchus. In addition, the distributions of several species of Leptodoras are expanded based on recent collecting efforts and identification of museum specimens not previously studied.
Resumo:
Two new species of Moenkhausia, one from the rio Tapajós and the other from the rio Xingu basins are described as apparently endemics of the Serra do Cachimbo. Both species, along with M. petymbuaba, share a distinct color pattern composed of large conspicuous dark blotches on the base of the body scales. Moenkhausia chlorophthalma, from rio Treze de Maio, a tributary to rio Curuá (rio Xingu basin), is distinguished by the presence of a proximal well delimited black area on the adipose fin and a green eye in life. Moenkhausia plumbea of the headwaters of tributaries of the rio Braço Norte, rio Tapajós basin is diagnosed by the presence of a dark longitudinal stripe across the eye and six branched pelvic-fin rays (vs. seven). Relationships of the new species with other Moenkhausia are discussed.
Resumo:
A new Astyanax species is described from several localities in the rio Negro, rio Solimões and lower rio Tapajós basins, Amazon basin, Brazil. The new species is distinguished from all remaining characids by its unique color pattern consisting of the combination of presence of a conspicuous, narrow dark midlateral stripe, a well-developed vertically-elongated dark humeral spot, and upper caudal-fin lobe and middle caudal-fin rays dark, with a rounded clear ocellated spot present at anterior third of caudal-fin lobe.
Resumo:
A new species of Leporinus Agassiz is described from the rio Curuá, a tributary of the rio Iriri, rio Xingu basin, Serra do Cachimbo, Pará State, Brazil. The new species is diagnosed by the color pattern, which consists of eight to ten midlateral round dark blotches plus 20 to 40 smaller ones scattered over the body, dental formula 3/4, subinferior to inferior mouth, 37 to 38 lateral line scales, 4/3-4 transversal series of scales, and 12 circumpeduncular scale series. The new species most closely resembles L. octomaculatus and L. reticulatus from the upper Tapajós basin, and L. marcgravii and L. microphthalmus from the rio São Francisco and the rio Paranaíba, respectively. Based on recently collected specimens, L. reticulatus is re-diagnosed as having an allometric elongation of the snout.
Resumo:
Objetivou-se com este estudo investigar característica ecológica e o hábito alimentar de Haemagogus e Sabethes em área epizoótica da febre amarela silvestre em duas localidades do Rio Grande do Sul, capturados com aspirador, armadilha de Shannon e puçá. Para identificação do sangue ingerido pelas fêmeas foi utilizada a técnica imunoenzimática ELISA de captura. Obteve-se maior atividade de Hg. leucocelaenus na primavera e outono, entre 12 e 17 horas, enquanto Sabethes albiprivus e Sa. quasycianus durante todo o ano. Para fêmeas de Hg. leucocelaenus em Santo Antônio das Missões, houve predomínio de sangue humano e para as demais espécies destaca-se a atratividade para bovinos nos dois municípios. A capacidade vetorial do Hg. leucocelaenus fundamenta vigilância entomológica em seu papel de estratificar áreas problemas ou a sustentabilidade do programa de imunização da população
Resumo:
Pimelodus multicratifer, a new species, is described from the rio Ribeira de Iguape basin. The new species differs from the other Pimelodus species by the following features: 26 to 30 gill rakers on the first branchial arch; a combination of three to six rows of dark spots regularly or irregularly scattered on the flanks and several small dark spots irregularly scattered on the dorsal surface of head, supraoccipital process, and sometimes on the dorsal and caudal fins; striated lips; maxillary barbels reaching between posterior tip of the pelvic-fin rays and posterior tip of the middle caudal-fin rays.
Resumo:
A second inseminating species bearing club cells organized into an anal-fin gland in sexually active males belonging to the genus Bryconadenos was recently discovered in the rio Xingu drainage and is described as new. It is distinguished from B. tanaothoros by the presence of a conspicuous dark blotch at the humeral region, and fewer scale rows between dorsal-fin origin and anal-fin origin. Males of B. weitzmani have longer pelvic fins at sizes beyond 30 mm SL. Bryconadenos weitzmani is further distinguished from B. tanaothoros by the cup shape of the anal-fin gland, its lower part much more developed than the upper, whereas in B. tanaothoros there is just a slit separating the almost equally developed upper and lower parts.
Resumo:
Ituglanis mambai, new species, is described from a cave in the Mambaí karst area, State of Goiás, Central Brazil. The new species distinguishes from epigean and cave congeners by the combination of the following characteristics: posterior supraoccipital fontanel absent; pectoral-fin rays usually i,7; six pleural ribs; total vertebrae 37-38 behind Weberian apparatus; shorter predorsal length (65.1-70.8% SL); shorter caudal peduncle length (8.4-11.9% SL); shorter dorsal-fin base length (7.7-11.3% SL); wider interobital width (29.2-36.5% HL); larger mouth width (43.4-64.0% HL); intermediate between epigean and other cave Ituglanis species as regards to both eyes (diameter varying from 0.5 to1.0 mm in adults, 7.8-10.1 % HL) and pigmentation, composed by irregular light brown spots along the body. The latter indicate the troglobitic status for I. mambai. In addition, this species has the maxillae with a discrete medial-posterior projection; fronto-lacrimal one half-length of the maxillae and pointed backwards; posterior process of palatine half its length, with a tenuous medial concavity; 14 dorsal and 12 ventral procurrent rays. In the natural habitat, I. mambai displayed cryptobiotic habits, trying to hide in the graveled bottom or under boulders when disturbed, apparently showing a negative response to light. It was observed a preference to slow-moving waters. Recent flood marks were observed in the stream conduit in March/April 2007 (end of the rainy season) when less individuals were observed on 300 m of the subterranean stream compared to September 2004 (end of the dry season).
Resumo:
Collections were made every two months in Ilha Grande Bay, Rio de Janeiro, for 21 months (August/2004-May/2006) to study the gametogenesis of Madracis decactis Lyman, 1859. A total of 1800 polyps were examined using standard histological techniques. Madracis decactis is a hermaphroditic species whose male and female gametes develop within different mesenteries. Oogenesis begins in October, while spermatogenesis begins at the end of February, both reaching maturity at the end of April. The peak of reproductive activity occurred between February and April, when all the polyps were fertile, containing mainly stage III oocytes. Examination of fertile polyps indicated the simultaneous presence of stages I, II and III for oogenesis and I, II, III and IV for spermatogenesis. No embryos or planulae were observed in the histological sections. The gametes or planulae spawning may occur between April and May.
Resumo:
Two new species of Hypostomus are described from the middle and upper rio Negro in Brazil. They are assigned to the Hypostomus cochliodon group (sensu Armbruster, 2003) by possessing few spoon-shaped teeth, and dentary angle averaging less than 80º. Hypostomus kopeyaka is described from the rio Tiquié, a tributary of the rio Uaupés, upper rio Negro basin, presents a unique color pattern among the Hypostomus species belonging to the Hypostomus cochliodon group, consisting of conspicuously horizontally elongated, closely-set black spots over the entire dorsal and lateral surfaces of the body. Hypostomus weberi is described from the middle rio Negro and can be distinguished from all remaining Hypostomus species belonging to the Hypostomus cochliodon group by possessing a unique color pattern consisting in large, rounded, widelyspaced black spots over body and fins.
Resumo:
Hemiancistrus cerrado is described from the tributaries of rio Araguaia, rio Tocantins basin. Hemiancistrus cerrado has external similarities with H. megalopteryx and H. punctulatus from coastal streams of southern Brazil, and can be distinguished by having a larger internarial width, 15.9-21.1% of head length (vs. 11.2-14.0% in H. megalopteryx and 11.2-13.9% in H. punctulatus) and, with little overlap, by the larger adipose-fin spine length, 9.4-13.6% of standard length (vs. 7.1-8.7% in H. megalopteryx and 7.4-10.0% in H. punctulatus). Hemiancistrus cerrado further differs from H. megalopteryx by having the pectoral-fin spine reaching maximally to the middle of the pelvic-fin spine when adpressed in adult males (vs. reaching tip). Hemiancistrus cerrado differs from other members of Hemiancistrus by color and numerous morphometric and meristic data.
Resumo:
Este estudo teve o objetivo de relatar a ocorrência de Trypanosoma vivax no Sul do Brasil. O protozoário foi diagnosticado em esfregaço sanguíneo de um bovino e a identificação baseada na morfologia das formas tripomastigotas e confirmada pela técnica de reação em cadeia de polimerases (PCR). O animal infectado apresentou sintomatologia compatível com a forma nervosa da infecção por T. vivax. Outros bovinos que compartilhavam o mesmo ambiente apresentaram resultados negativos para T. vivax por PCR. Este é o primeiro registro de T. vivax no Estado do Rio Grande do Sul e na região Sul do Brasil.
Resumo:
OBJETIVO: Verificar a associação entre relato de sibilância em crianças e adolescentes e o local de residência em relação à dispersão dos poluentes atmosféricos emitidos pelo Pólo Petroquímico (PPQ) de Guamaré (RN). MÉTODOS: Estudo transversal de relato de sibilância em crianças e adolescentes de 0 a 14 anos de idade, residentes no entorno do PPQ de Guamaré, em 2006. Foi utilizado o questionário padronizado do International Study of Asthma and Allergies in Childhood, acrescido de questões relativas ao tabagismo, renda, moradia e escolaridade. Concentrações diárias de PM10, PM2,5, carbono grafítico, SO2, NO2, O3, benzeno, tolueno e xilenos foram medidas em uma estação de monitoramento fixa. As comunidades residentes na área de influência das emissões do PPQ foram classificadas, segundo a direção preferencial dos ventos, em expostas e de referência. RESULTADOS: Participaram do estudo 209 crianças e adolescentes. As concentrações médias diárias dos poluentes monitorados mantiveram-se abaixo dos limites estabelecidos nos padrões de qualidade do ar. A prevalência de sibilos nos últimos 12 meses foi de 27,3%. Associações estatisticamente significantes com sibilos nos últimos 12 meses foram verificadas mesmo após ajustamentos para comunidades expostas [razão de chances (odds ratio, ORajust) = 2,01; intervalo de confiança de 95% (IC95%) 1,01-4,01], gênero masculino (ORajust = 2,50; IC95% 1,21-5,18) e idade de 0 a 6 anos (ORajust = 5,00; IC95% 2,41-10,39). CONCLUSÃO: Mesmo em baixas concentrações de poluentes atmosféricos, a ocorrência de sintomas respiratórios em crianças e adolescentes nas comunidades no entorno de um PPQ esteve associada a residência na direção preferencial dos ventos, mostrando-se mais vulnerável o grupo de pré-escolares do gênero masculino.
Resumo:
Structural analysis carried out on a segment of the Neoproterozoic Ribeira Belt, southeastern Brazil, show that it represents part of the transpressive dextral orogen related to the Central Mantiqueira Province. NNE-trending and steeply dipping regional mylonitic belts form anastomosed geometry, and describe a map-scale, S-C-like structure that is characterized by their deflection towards NE near the Além Paraíba Lineament. Lithological and structural control related to deformation partition were responsible for the formation of felsic mylonitic granulites with S-type granites lenses developed in ductile shear zones, alternated with less deformed intermediate to basic granulites associated with charnockites. The dextral shear sense indicators are consistent with transpressive deformation in the region and are common especially at the border of the main shear zones. The presence of S-type leucogranite may lead to variations of linear and planar relationships, which result in local extension zones. These elements are consistent with oblique continental collision considering the São Francisco Craton as a stable block.
Detecção de contaminantes em espécie bioindicadora (Corbicula fluminea) - Rio Ribeira de Iguape - SP
Resumo:
The study assessed heavy metal concentrations in the tissue samples of Corbiculafluminea, by ICP-OES. In the tissues, average levels of 23.99 µg/g of Cu, 144.21 µg/g of Zn, 0.71 µg/g of Cd, 7.10 µg/g of Cr and 2.41 µg/g of Pb were detected ahowing that this last value is high and above the ANVISA reference (2.00 µg/g) for fish and other products. The results suggest that natural processes occuring in the Ribeira de Iguape River are not sufficient for purification so that metals remain in the water and can accumulate in the trophic chain.