774 resultados para South-eastern Queensland
Resumo:
The crustacean species composition in the intertidal zones of 13 sheltered unconsolidated marine beaches in south-eastern Brazil is described. Fifty-three crustacean species were collected, adding 46 species to the total reported by previous studies in the same region. Decapods dominated the community, in contrast to exposed sandy beaches where peracarids normally predominate. The species were distributed irregularly among the beaches. Richness varied markedly among sites, and was positively related to a combination of factors such as fine sand grains, high organic matter content, and relatively low silt-clay content. The presence of rock fragments enabled both rocky shore and sandy beach crustaceans to occur oil the same beaches. Richness and abundance of crustaceans showed no clear relationship to sediment grain size and slope, in contrast to the norm for exposed sandy beaches. The dominance of the tanaid Kalliapseudes schubarti in sonic areas may be a result of organic matter pollution in the region. These beaches showed higher species richness than typical sheltered and exposed sandy beaches, indicating that this sheltered, highly heterogeneous seascape is an important area for conservation.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Eighteen collections of red-coloured Audouinella from Central Mexico and southeastern Brazil detected three species. The most common species, A. eugenea, is characterized by macroscopic thalli, the erect system consisting of filaments with cylindrical cells, undifferentiated into proximal and distal parts, and relatively large monosporangia (greater than or equal to 12.0 mum long). Spermatangia. and possible propagules were observed in some Mexican populations. This is the third Audouinella species observed to have gametangia and the first member of the Acrochaetiales with putative propagules. The second species, from Central Mexico, was characterized by the following features: macroscopic thalli, the erect system differentiated into proximal parts with cylindrical cells, unbranched or rarely branched, and distal parts with barrel-shaped cells, abundantly branched to form dense fascicles, with alternate or dichotomous branching, some at right-angles to the axis, and relatively large monosporangia (greater than or equal to 12.0 mum long). The morphologically distinct proximal and distal portions of the erect system, the latter forming dense fascicles, was a consistent character so far unknown in Audouinella; thus, we propose a new species, A. huastecana sp. nov. The third species is a microscopic epiphyte, A. meiospora, with a well-developed prostrate system composed of creeping and loosely aggregated filaments, and a short homogeneous erect system (less than or equal to 15 cells) of filaments with cylindrical or barrel-shaped cells and small monosporangia (less than or equal to 13.0 mum long). A. eugenea and A. meiospora are characterized for the first time from the Southern and Northern Hemispheres, respectively, both occurring mostly in areas of tropical or subtropical rainforests. A. meiospora is reported from new macroalgal hosts. A. eugenea and A. huastecana tended to occur in warm, alkaline waters with a high ion content that were moderate to fast flowing, whereas A. meiospora was not associated with particular habitats.
Resumo:
Forty-three specimens of Leptodactylus podicipinus (Anura: Leptodactylidae) were collected in the south-eastern Pantanal, municipality of Corumba, State of Mato Grosso do Sul, Brazil in February and July 2007, and examined for endoparasites. Forty (93%) specimens were infected with at least one helminth species. The predominant parasites were nematodes (Aplectana sp., Cosmocerca podicipinus, Oswaldocruzia lopesi, Physalopteroides venancioi, Rhabdias sp.), but the trematode Catadiscus propinquus also showed high prevalence. The trematodes Infidum infidum and Travtrema stenocotyle were also found, but in only one specimen. Adult frogs showed higher parasite diversity than subadults. Leptodactylus podicipinus was preferentially infected by direct life-cycle parasites and was reported as a new host record for seven helminth species.
Resumo:
This study examines the ecology of a population of Geoffroy's side-necked turtle Phrynops geoffroanus inhabiting a polluted urban river in Ribeirão Preto city, São Paulo state, south-eastern Brazil. Adult turtles fed mainly on Chironomidae larvae and pupae (Chironomus cf. plumosus, 100% of occurrence frequency) and domestic waste, but they also consumed terrestrial items (cockroach, snails) and carrion. Juvenile turtles showed more feeding diversity than the adults and exhibited a trend for predation on Chironomidae pupae, but this is not reflected in resource partitioning. The elevated number of turtles (170-230 turtles/ha of river) and biomass (255-345 kg/ha of river) inhabiting this urban river is probably the result of the abundance of sewage and organic waste produced by humans, the absence of predators, and increased availability of nesting areas. Such factors convert this area into an environment highly advantageous for the survival of Geoffroy's side-necked turtle.
Resumo:
Thirteen populations of Thorea were analyzed from central Mexico and south-eastern Brazil. All populations were considered as belonging to a single species [Thorea hispida (Thore) Desvaux], with wide variation of morphological features. Secondary branches varying in frequency were observed in several populations with an overlapping in the range of branch density for Thorea violacea Bory and T. hispida (0-9 and 11-41 per 30 mm, respectively). As this is the most distinguishing character and on the basis of the overlapping (within a same population or even a single plant), we regarded T. violacea as a synonym of T. hispida. 'Chantransia' stage in culture, as well as gametophyte and carposporophyte were described in detail. We confirmed the coexistence of asexual monosporangia with sexual reproductive structures (carpogonia and spermatangia) and carposporangia. Size, content, arrangement and chromosome number were the most distinctive characteristics among spermatangia, carposporangia and monosporangia. Monosporangia can be promptly differentiated from spermatangia by their granulated content and larger size but they are similar to carposporangia in shape and size; however, monosporangia are not arranged in fascicles. Structures resembling bisporangia were observed in female plants of some populations. Chromosome numbers were n = 4 for spermatangia and fascicle cells, and 2n ca8 for gonimoblast filaments, carpospores and the 'Chantransia' stage cells. The populations of Thorea from central Mexico and south-eastern Brazil corroborated the known world distribution for T. hispida, consisting dominantly of tropical to subtropical rainforests, sometimes extending into warm temperate areas. Thorea hispida occurred in warm (temperature 17.6-28.0°C), neutral to alkaline (pH 7.0-8.0), high ion content (specific conductance 59-2140 μS cm-1), moderate flowing (current velocity 17-43 cm/s) and shallow waters (depth <50 cm); these data are essentially similar to previous reports.
Resumo:
Studies focusing on communities of helminths from Brazilian lizards are increasing, but there are many blanks in the knowledge of parasitic fauna of wild fauna. This lack of knowledge hampers understanding of ecological and parasitological aspects of involved species. Moreover, the majority of research has focused on parasitic fauna of lizards from families Tropiduridae and Scincidae. Only a few studies have looked at lizards from the family Leiosauridae, including some species of Enyalius. This study presents data on the gastrointestinal parasite fauna of Enyalius perditus and their relationships with ecological aspects of hosts in a disturbed Atlantic rainforest area in the state of Minas Gerais, south-eastern Brazil. Two nematode species, Oswaldocruzia burseyi [(Molineidae) and Strongyluris oscari (Heterakidae) were found. Nematode species showed an aggregated distribution in this host population, with O. burseyi being more aggregated than S. oscari. The present study extends the range of occurrence of O. burseyi to the Brazilian continental area. © 2011 Cambridge University Press.
Resumo:
This study presents new information on feeding habits of Guiana dolphins, Sotalia guianensis, in south-eastern Brazil, together with new regression equations to evaluate the weight and length of fish from otoliths, showing an overview on the knowledge about this species-diet in this area. Eighteen stomach contents had been analysed and compared to 180 samples collected in another eight feeding studies. The analysed specimens were either incidentally caught in gillnets used in coastal waters by the fleet based in the Cananéia main harbour (25°00âS 47°55âW), south of São Paulo State, or found dead in inner waters of the Cananéia estuary between 2003 and 2009. Based on the index of relative importance analysis, the most important fish species were the banded croaker, Paralonchurus brasiliensis. Doryteuthis plei was the most representative cephalopod species. Stellifer rastrifer was the most important fish species observed in dolphins in inner estuarine waters and P. brasiliensis in recovered dolphins from coastal waters. Loliguncula brevis is the only cephalopod species reported from dolphins found in inner estuarine waters up to date. Doryteuthis plei was the most important cephalopod species observed in coastal dolphins. When considering other feeding studies, the most representative fish family in the diet of S. guianensis was Sciaenidae, which is mainly represented by demersal fishes. The main preys of S. guianensis are abundant in the studied areas, which may indicate an opportunistic feeding habit. The majority of them are not the most important target species by the commercial fishery in south-eastern Brazil. © 2012 Marine Biological Association of the United Kingdom.
Resumo:
The population dynamics, including the sex ratio, reproductive period, individual growth and longevity, and population structure of the shrimp Xiphopenaeus kroyeri, are described. The shrimps were collected monthly from July 2005 to June 2007 at four sites in Ubatuba Bay, Brazil. The salinity, temperature, depth, organic matter content and sediment grain size were measured at each site. Specimens were quantified and sexed, their carapace length measured and their gonads were classified according to the stage of maturation. A von Bertalanffy model was used to estimate the individual growth, and longevity was calculated using its inverted formula. In total, 6 470 individuals were examined and the number of males and females differed significantly in favour of females. During some periods, the segregation could be related to the reproductive period. Reproductive females were captured throughout the sampled period, and there were biannual peaks that were followed by peaks of juveniles. Carapace growth was less for males than for females, which is likely related to oocyte production and the higher fecundity of the females. The higher probability of female capture can be related to their longer foraging to sustain the enhanced food requirement during the ovarian maturation period. © 2013 Copyright NISC (Pty) Ltd.