Repositório RCAAP

Feeding of Pitangus sulphuratus (Tyrannidae) nestlings have been poorly studied. Here we describe the foraging behavior of a P. sulphuratus pair and the searching and offering time of food items to nestlings in the Pantanal, Brazil. Data collection was carried out over 25 days on the outskirts of the Base de Estudos do Pantanal building, inhabited by insectivorous bats. Records were based on direct observations with the help of binocular. The pair required little time for searching for small insects and fruits, but these items comprised a little amount of food per event of capture. Some large prey was more time-costly for searching, but the long period that these food items were offered to nestlings overcompensated the searching time. Considering the time of feeding nestlings (benefit) in relation to the searching time by the parents (cost), bats and snails are the most advantageous items for P. sulphuratus parents feeding nestlings at the study site.

Community functioning may be affected by functional diversity, which measures the extent of complementarity in resource use. We tested whether there was a relationship between functional diversity of woody species and community functioning on a fine scale, using FD as a measure of functional diversity and litter decomposition rate as a surrogate for community functioning. We measured eight functional traits from a woodland cerrado community in southeastern Brazil. Then, we tested the correlation between FD and the decomposition rate taking into account differences in soil features and between decomposition rate and each trait separately. The decomposition rate was related to the aluminium and phosphorus concentration in soil, but not to FD, pointing out that functional diversity was not a good predictor of community functioning. There was a non-significant relationship between FD and the decomposition rate even when we considered each trait separately. Most studies in the relationships between biodiversity and community functioning on fine scales were carried out by experimental manipulation of diversity and in temperate regions. We carried out this fine scale study as a mensurative experiment and in a tropical savanna. Our findings indicated that the relationship between biodiversity and community functioning is not as straightforward as usually assumed.

Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate wastewater quality following an ECF cellulose bleaching process. The results revealed a toxic effect of the effluent, with inhibition of meristem growth and generally lower values of metaphase, anaphase and telophase indices at pH 10.5 than pH 7 for all effluent concentrations. The genotoxicity effect was different from the toxic effect given that the micronucleus and the chromosomal aberration tests in anaphase-telophase cells were low over all ranges of the studied effluent concentrations.

The fluctuation of the population of Daphnia laevis in Lake Jacaré (Middle River Doce, Minas Gerais) was monitored monthly (at one point in the limnetic region) for six years (2002-2007) as part of the Program of Long-Term Ecological Research (LTER/UFMG). The following parameters were also monitored: water temperature, pH, electrical conductivity, dissolved oxygen, chlorophyll a, total phosphorus, phosphate, total nitrogen, nitrate, nitrite, ammonia, and densities of Chaoborus and ephippia of Daphnia laevis in the sediment. A seasonal pattern was observed in the fluctuation of D. laevis, with higher densities recorded during periods of circulation (May-August). A significant correlation was found between the density of D. laevis and temperature (r = -0.47, p = 0.0001), chlorophyll-a (r = -0.32, p = 0.016) and indicators of the lake's trophic status (total phosphorus, r = 0.32, p = 0.007 and trophic state, r = 0.36, p = 0.003), as well as Chaoborus density (r = 0.43 and p = 0.002). These results indicate that changes in the physical and chemical characteristics of the water related with stratification and circulation of the lake may have a direct (temperature, total phosphorous) or an indirect (food availability, presence of predators, ephippia eclosion) influence on the fluctuation of the D. laevis population.

To evaluate the effects of macrophytes presence in the structure of littoral fish assemblages in the littoral zone, monthly samples were collected from September, 2006 to August, 2007 in an impounded tributary of the Itá Reservoir, the Fragosos River, located in the Upper Uruguay River Basin. Fish were collected using a beach seine and sampling was conducted in the littoral zone inside a macrophyte stand and in an area with no macrophytes. A total of 5,191 fish were captured during the study period. Fish assemblage attributes (fish abundance, species richness, and diversity) varied significantly between sampling months and areas. The abundance of Astyanax cf. bimaculatus, Astyanax fasciatus, Geophagus brasiliensis, and Gymnotus carapo also varied significantly between sampling months and areas. Detrended Correspondence Analysis showed a clear spatial segregation at the first axis and a slight temporal segregation at the second axis. These results were confirmed by Multiple Response Permutation Procedure analysis. Apparently, the presence of the aquatic macrophytes is not the only factor influencing the distribution of littoral fish assemblages in the Fragosos River. Littoral fish seem to be taking advantage of low- to medium-sized macrophyte stands, but few species used maximum-sized stands.

There has been a resurging interest in patterns of β-diversity, especially by the mechanisms driving broad-scale, continental and global patterns, and how partitioning β-diversity into richness (or nestedness) and turnover components can be linked with such mechanisms. Here we compared two recent methodologies to find richness and turnover components of β-diversity, using a large regional scale dataset of mammal, bird, reptiles and amphibian species found in seven regions of Central, North and Northeastern Brazil. As well as a simple comparison of the metrics available, we analyzed spatial patterns (i.e., distance-decay similarity) and the effects of biome type in these components using raw and partial Mantel tests. Our analyses revealed that turnover estimated using Baselga's (2010) approach is slightly higher than the estimate using Carvalho's et al. (2012) approach, but all analyses show consistent spatial patterns in species turnover using both methods. Spatial patterns in β-diversity revealed by Mantel tests are also consistent with expectations based on differential dispersal abilities. Our results also reinforce that spatial patterns in β-diversity, mainly in the turnover components expressing faunal differentiation, are determined by a mix or broad scale environmental effects and short distance spatially-structured dispersal.

The brine shrimp (Artemia salina Leach) lethality bioassay offers an advantage in standardization and quality control of botanical products. This test is well correlated with antitumor activity (cytotoxicity) and can be used to monitor the activity of bioactive natural products. This paper reports the bioactivity of ethanol extracts from seven medicinal plants from the Northeast of Brazil (Acmella uliginosa, Ageratum conyzoides, Eugenia uniflora, Plectranthus neochilus, Moringa oleifera, Justicia pectoralis and Equisetum sp.) against Artemia salina. Biological activity was evaluated for extracts at 1, 10, 100, and 1000 µg/mL in triplicate, and the mean lethal concentration values (LC50) were obtained by probit analysis. The species Acmella uliginosa showed the highest bioactivity, and its flower extract was more active than its leaf extract.

Most natural forests have been converted for human use, restricting biological life to small forest fragments. Many animals, including some species of bats are disappearing and the list of these species grows every day. It seems that the destruction of the habitat is one of its major causes. This study aimed to analyze how this community of bats was made up in environments with different sizes and quality of habitat. Data from studies conducted in the region of Londrina, Parana, Brazil, from 1982 to 2000 were used. Originally, this area was covered by a semi deciduous forest, especially Aspidosperma polyneuron (Apocynaceae), Ficus insipida (Moraceae), Euterpe edulis (Arecaceae), Croton floribundus (Euforbiaceae), and currently, only small remnants of the original vegetation still exist. The results showed a decline in the number of species caught in smaller areas compared to the largest remnant. In about 18 years of sampling, 42 species of bats were found in the region, representing 67% of the species that occur in Paraná and 24.4% in Brazil. There were two species of Noctilionidae; 21 of Phyllostoma; 11 Vespertilionidae and eight Molossidae. Eight of these were captured only in the largest fragment, Mata dos Godoy State Park (680 ha). Ten species had a low capture rate in the smaller areas with less than three individuals. Of the total sampled, 14 species were found in human buildings, and were able to tolerate modified environments, foraging and even using them as shelter. As the size of the forest area increases, there is a greater variety of ecological opportunities and their physical conditions become more stable, i.e., conditions favorable for growth and survival of a greater number of species. Forest fragmentation limits and creates subpopulations, preserving only long-lived K-strategist animals for some time, where the supporting capacity of the environment is a limiting factor. The reduction of habitats, species and genetic diversity resulting from human activities are endangering the future adaptability in natural ecosystems, which promotes the disappearance of low adaptive potential species.

Studies on Neotropical aquatic macrophytes have increased in recent decades, however species richness in wetlands of South America is far from being fully known. In addition, studies having an ecological approach are scarce in the Pantanal. Rapid assessments are essential for gaining knowledge of the biodiversity in the region. This study was performed in five sites of the Baía do Castelo, the western border of the Brazilian Pantanal, which included wild-rice patches, floating mats and floating meadows. At each site, plots of 0.5 × 0.5 m were set (n = 137), species of aquatic macrophytes were identified, their coverage was measured and the plot depth was estimated. We recorded 57 species in 26 families, of which Poaceae was the richest. The most frequent and abundant species was Commelina schomburgkiana; the second most frequent was Oryza latifolia,followed by Leersia hexandra, Enydra radicans and Pityrogramma calomelanos. The latter species was second in cover, followed by Pontederia rotundifolia, Eichhornia azurea, E. crassipes and Enydra radicans. These five species and C. schomburgkiana (the most abundant) together represent more than half of the coverage on the lake. Pontederia rotundifolia, Ludwigia helminthorrhiza, Pistia stratiotes, E. azurea, E. crassipes, Enydra radicans and Panicum elephantipes were strongly associated with deeper areas, while Oryza latifolia, Leersia hexandra and Salvinia auriculata were prevalent in shallow areas. Pityrogramma calomelanos, Ludwigia nervosa, Ipomoea alba, Cayaponia podantha, Polygonum acuminatum, Rhynchanthera novemnervia and Ludwigia leptocarpa were highly correlated with floating meadows. The structure of the habitat, natural dynamics and zonation of aquatic vegetation in the Baía do Castelo seems to be influenced by a variation in water levels, which promotes spatial segregation, most likely due to competition and/habitat preference.

Environmental conditions favor the predominance of dense populations of cyanobacteria in reservoirs in northeastern Brazil. The aim of this study was to understand cyanobacterial population dynamics in the rainy and dry seasons at two depths in the Arcoverde reservoir. Microalgae and cyanobacteria samples were collected during 24 hours with intervals of 4 hours (nycthemeral) at sub-surface and 10 m using a van Dorn bottle and a determined biomass. Physical and chemical variables were obtained and the data were analyzed using the principal component analysis (PCA). No nycthemeral variations in the taxonomic composition or distribution of the populations of cyanobacteria were found between the different times of day in either the rainy or dry season. In both seasons, the greatest biomass of the phytoplankton community was made up of cyanobacteria at two depths and all times of the day. Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju was dominant at all times of the day on both the surface and at the bottom. In the rainy season, the differences in cyanobacterial biomass between the surface and bottom were less significant than in the dry season. The differences in cyanobacterial biomass between surface and bottom were less pronounced than those found in the dry season. We concluded that a) physical variables better explain the alterations of species in the phytoplankton community in an environment dominated by cyanobacteria throughout the year; b) seasonal climatic factors associated to periods of stratification and de-stratification are important for alterations in the community and variations in biomass and, c) the turbidity caused by rainfall favored the emergence and establishment of other cyanobacteria, especially Planktothrix agardhii (Gomont) Anagnostidis & Komárek.

The unionid Anodontites trapesilais (Lamarck, 1819) like most freshwater mussels is a parasite of fish. So it is trivial to assume that the availability of hosts is an important factor for the maintenance of unionoid populations. What seems obvious is not always so easy to demonstrate. This study proposes to investigate the effects of abiotic and biotic variables related to the incubation of larvae in A. trapesialis. For this, we estimate different biological indexes and try to capture the dimensionality of the fish, along with the temporal variation of environmental variables. From the application of a CCA, it was demonstrated that there was a synchronicity among the factors and variables proposed here, and we infer that the flood pulse acts as a synergistic factor in this process.

The Atlantic Rain forest, which is considered the second largest pluvial forest in the American continent, has had an estimated 93% of its original area destroyed. Although studies concerning the herpetofaunal diversity in this biome have been intensified in the past years, its diversity is still underestimated. The Nucleo Experimental de Iguaba Grande (NEIG) is included in an Environmental Protection Area (APA de Sapeatiba) in the Iguaba Grande municipality, Rio de Janeiro state, Brazil (22º 51' S and 42º 10' W). The goal of this study was to conduct an inventory of the reptile and amphibian species that occur in this area between July 2008 and December 2009. We recorded 19 species of amphibians (18 anurans and one caecilian) and 15 species of reptiles (three lizards, 11 snakes and one amphisbaenian). Leptodactylus latrans and L. mystacinus had the highest capture rates among amphibians captured, and among reptiles, Ameiva ameiva, Hemidactylus mabouia and Mabuya agilis had the highest capture rates. Rarefaction curves for both amphibians and reptiles did not reach the asymptote, indicating that the species richness in the NEIG is still underestimated.

The first and only study on gastrointestinal parasites of wild rodents in the Island of Santa Catarina was done in 1987. The aim of this study was to identify intestinal parasites from wild rodents in Santo Amaro da Imperatriz and Santa Catariana Island, and to compare the richness and composition of the gastrointestinal parasite community of both areas. Rodents were captured with live traps, and feces were screened using the sedimentation method and optical microscopy. The following species of rodents were captured in the two areas: Akodon montensis, Euryoryzomys russatus, Oligoryzomys nigripes and Nectomys squamipes. In Santo Amaro da Impetratriz, prevalent parasites were: A. montensis (51%), E. russatus (62%), O. nigripes (53%) and N. squamipes (20%). From the Island of Santa Catarina the rodent prevalence rates were: A. montensis (43%), E. russatus (59%), O. nigripes (30%) and N. squamipes (33%) and the collected parasites were: Hymenolepis sp., Longistriata sp., Strongyloides sp., Hassalstrongylus sp., Syphacia sp., Trichomonas sp., Ancylostomidae, Trichuridae, Oxyuridae and Eucoccidiorida. The species richness (10.6 ± 0.7) of the endoparasite comunity in the area located on the continent was higher (p < 0.01) and different (p = 0.001) from that of the area located on the island (6.9 ± 0.5).

This study characterized the reproductive cycle of the stout razor clam Tagelus plebeius in the estuary of the Cachoeira River, Ilhéus, Bahia, northeastern Brazil. Samples of 20 animals per collection were taken biweekly from August 2005 to August 2006. The 480 specimens were measured on the antero-posterior axis (length) and then removed from the shell. After macroscopic analysis, the gonads were fixed in Davidson's solution, processed by routine histology and stained by Harris hematoxylin and eosin. The gonads of both males and females appeared milky white, without sexual dimorphism. Microscopic analyses indicated a M: F ratio of 1.06: 1 and continuous reproduction of T. plebeius in the region. The period from August to October showed the most intense spawning. This study provides another example of continuous reproduction of bivalves in tropical waters, and because this species is a heavily exploited fishery resource in the region, it draws attention to the need for a management plan aimed at reducing harvests.

Borrelia burgdorferi, the agent of Lyme borreliosis, is a spirochetes transmitted by ticks to humans and animals. Its cultivation in vitro in tick cells allows studies of its biology and provides methodology for future research in Brazil, and for the isolation of Borrelia spp. We examined in vitro the characteristics of embryonic cells of Rhipicephalus microplus and Amblyomma cajennense in cell culture and investigated the suitability of embryonic cells as a substrate for cultivation of B. burgdorferi. Subcultures were prepared from primary cultures of embrionary cells of R. microplus and A. cajennense maintained in Leibovitz's (L-15) complete medium at 28 ºC and 31 ºC, respectively. When a monolayer had formed, the L-15 was replaced with Barbour-Stoener-Kelly medium for experiments to infect cell cultures with B. burgdorferi. After 72 hours of cultivation, the spirochetes were counted using an inverted phase contrast microscope and dark-field illumination (400×). Survival, multiplication and the adherence of B. burgdorferi for embryonic cells of R. microplus and A. cajennense were observed. B. burgdorferi cultured with embryonic cells of R. microplus grew on average to a density (final count) of 2.4 × 10(7) spirochetes/mL, whereas in cell-free culture, an average of 2.5 × 10(7) spirochetes/mL were counted. When cultivated with A. cajennense cells, the final count of spirochetes was on average 1.7 × 10(7) spirochetes/mL, while spirochetes cultured under cell-free conditions replicated on average of 2.2 × 10(7) spirochetes/mL. Similar results were observed in the final count of Spirochetes cultivated in cells of R. microplus and A. cajennense, when compared with cell-free control. These results demonstrated that cells of R. microplus and A. cajennense have the potential to be used as growth substrate for B. burgdorferi in the study of its interaction with host cells.

Thirty-two specimens of Columbina picui (picui ground-dove) were examined, and a collection of arthropods was made by washing the external surface of the body and the nasal cavity. The species in the order Phthiraptera found and their respective prevalences, mean abundance and mean intensity were: Columbicola passerinae (84.4%; 10.3; 12.2), Hohorstiella passerinae (21.9%; 0.7; 3.1) and Physconelloides eurysema (3.1%; 0.1; 2). The gamasid mites found in the birds and their respective prevalences, mean abundance and mean intensity were: Pellonyssus marui (31.3%; 1.2; 3.9), Ornithonyssus bursa (15.6%; 0.2. ;1.2) and Mesonyssus sp. (6.3%; 0.1; 1). Columbicola passerinae, H. passerinae, P. eurysema, O. bursa, P. marui and Mesonyssus sp. were recorded for the first time infecting C. picui in Brazil. Except for O. bursa, the other species are reported for the first time in the state of Rio Grande do Sul, Brazil.

The edge of a forest fragment can be considered a zone of transition between the interior of the fragment and the surrounding habitat matrix. Plants along the edge are more exposed to disturbance and microclimate variation than interior plants, resulting in the so-called edge effect. In this study, we compared leaf area, fluctuating asymmetry and chemical (water, nitrogen and tannins) leaf traits between Erythroxylum tortuosum plants inhabiting the edge with those growing in the interior of a cerrado fragment in Brazil. We also describe the temporal variation in the vegetative and reproductive phenological events of E. tortuosum plants throughout the season. Nitrogen, leaf area and fluctuating asymmetry did not differ between the two plant groups. Young leaves of the edge plants had significantly higher levels of tannins and lower levels of water than those of interior plants. We suggest that differences in leaf chemical concentrations between edge and interior plants may occur due to factors such as light intensity, wind, temperature and leaf age rather than plant stress. With respect to plant phenology, most reproductive events occurred during the spring. Leaf buds and young leaves prevailed during the rainy season. In the dry season, however, the vegetative events decreased due to leaf senescence followed by leaf abscission.

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

The purpose was to show that displacements, promoters of genetic diversity in metapopulations, increase the probability of survival of bat species adapted to medium and long-distance flights. Samples were taken in four forest fragments, distributed in three municipalities in northern Paraná, and the maximum distance between the studied areas is 20 km. A monthly sampling was performed for each fragment, for the period of July 2008 to June 2009. We used eight nets for collection which remained open during the first four hours of the night, totalling 192 hours during a year of study. The marking occurred from October 2008 to March 2009 and was accomplished through the use of anodised metal rings of four different colours. One hundred and fifty individuals were banded and since the first capture, four displacements were recorded. After five months of collecting and marking, one Carollia perspicillata was found three km away. Two Artibeus lituratus were recorded about 20 km from the marking place: the first one after 22 months and the second one after 24 months. Additionally, one Platyrrhinus lineatus was captured at about 20 km, after 26 months. As they moved around over considerable distances and are not monogamous, they mate with females of other fragments, exchanging genes and reducing or even avoiding inbreeding. Thus, populations of bats have the ability to increase genetic diversity in metapopulations, provided by displacements between the forest fragments. Species that behave like this are not vulnerable to isolation.

New hosts and parasitism notes for the mite Leptus (Acari: Erythraeidae) in Brazil. Larval erythraeid mites are common ectoparasites of harvestmen (Opiliones). Studies describing insects as potential hosts have received little attention. Specimens of an undescribed species of the genus Leptus were collected in association with predatory and phytophagous Heteroptera bugs in a secondary forest in Viçosa, Minas Gerais state, Brazil. New mite-host records and information on seasonality of this mite are presented.