Repositório RCAAP

Biological control has been reducing the use of chemical products against insect pests, specially predatory Pentatomidae. Species of this group can present high variations in their life cycle as a result of their diet. Thus, the objective of this research was to study nymph development and reproduction of Podisus distinctus (Stäl, 1860) (Heteroptera: Pentatomidae) fed on Bombyx mori L., 1758 (Lepidoptera: Bombycidae) larvae (T1), compared to those fed on Tenebrio molitor L., 1758 (Coleoptera: Tenebrionidae) (T2) and Musca domestica L., 1758 (Diptera: Muscidae) larvae (T3) at a temperature of 25 ± 0.5ºC, relative humidity of 70 ± 2%, and photophase of 12 h. Predators fed on B. mori showed duration of the nymph phase (18.68 ± 1.02) similar to those fed on T. molitor (18.32 ± 1.49). Pre-oviposition and oviposition periods and number of egg masses, besides eggs and nymphs per female, were higher with B. mori (5.83 ± 2.02; 15.00 ± 7.40; 8.42 ± 1.84; 296.69 ± 154.75; and 228.55 ± 141.04, respectively) while longevity of males and females of P. distinctus was 25.76 ± 16.15 and 35.00 ± 16.15 days with T. molitor, and 20.57 ± 13.60 and 23.46 ± 12.35 days with B. mori, respectively.

In this paper we calculate the values of eight pattern detection indices, using different quadrat sizes where individuals of angico above 1.5 m were located, in order to examine their statistical behaviour with increasing sample size. It was concluded that the best index is the standardized Morisita index (Ip) which is completely independent of sample size.

The insect marking technique of Tadei & Mourão (1976) is until now the only experimental method allowing real-age determination of each individual in a population and, consequently, determination of age structure in a given population. We propose an improvement of this technique, used here to determine the population age structure of the geographical strain SR of the Megaselia scalaris Loew (Diptera; Phoridae), maintained by serial transfer technique at constant temperatures 25 ± 1.0ºC and 20 ± 1.0ºC. Determining the age structure allowed the calculation of the real longevity of the flies and the identification of the effect of temperature decisive factors in these are the technique of marking insects, because otherwise we would only have an estimate, and depending on mistakes there in, the effect of the determinant factor (temperature) cannot be detected.

The age and growth of the pintado Pseudoplatystoma corruscans were studied during the period from May 1994 to May 1995. The standard length ranged from 52 to 145 cm and the weight from 1.3 to 41 kg. The biometric relationship between the standard length (Ls) and total length (Ltotal) and between the total weight (Wt) and the standard length (Ls) were obtained for the species, being respectively: Ltotal = 3.296 + 1.069 * Ls and Wt = 0.00624 * Ls3.134.The condition factor calculated monthly suggests the spawning season to be between the months of February and March. The age was estimated by counting growth rings present in the spines of the pectoral fins, and 10 age classes were detected. The mean distance of the last ring until the border of the spine suggests that the period of least growth is between July and September (dry period). Von Bertalaffy's equation describing the growth of the pintado is: Lt = 183 * [1 - exp - 0.085 * (t + 3.274)]. Total mortality was Z = 0.24 year-1 and natural mortality M = 0.20 year-1. As the present level of exploitation, F = Z - M = 0.04 year-1, we conclude that the pintado stock was still underexploited in the Pantanal in the sampled period.

Increased environmental pH decreases ammonia transport through the gills, impairing nitrogenous waste. The consequent toxicity is usually drastic to most fishes. A few species are able to synthesize urea as a way to detoxify plasma ammonia. We studied three teleosts of the family Erythrinidae living in distinct environments, and assumed the biochemical behaviors would be different in spite of their being closely related species. Adult fish collected in the wild were submitted to alkaline water and the urea excretion rate was determined. The specific activity of urea cycle enzymes was determined in liver samples of fish from neutral waters. The studied species Hoplias lacerdae, Hoplerithrynus unitaeniatus, and Hoplias malabaricus are ureogenic. Urea synthesis is not a metabolic way to detoxify ammonia in H. lacerdae and Hoplerithrynus unitaeniatus exposed to an alkaline environment. The plasma ammonia profile of both species showed two distinct biochemical responses. Urea excretion of H. malabaricus was high in alkaline water, and the transition to ureotelism is proposed. The nitrogen excretion rate of H. malabaricus was among the highest values reported and the high urea excretion leads us to include this species as ureotelic in alkaline water.

Electrokinetic, thermic, and kinetic properties of products of NADP-dependent isocitrate dehydrogenase (IDHP; EC 1.1.1.42) loci of Astyanax scabripinnis (Pisces, Characidae) collected at three different altitudes (700 m, 1,800 m, and 1,920 m) of Grande Stream at Campos do Jordão, State of São Paulo, Brazil, were analyzed. Two IDHP bidirectionally divergent loci, a single skeletal muscle, the IDHP-A*, and a single liver IDHP-B*, both polymorphic, were detected in the three different altitude populations. The variant allele *128 at the IDHP-A* locus, had its highest frequency detected in the 1,920 m population (0.494). Among the nine variant alleles detected at the IDHP-B* locus (*37, *57, *69, *79, *85, *114, *119, *124, and *140), the *37 and 79 were detected only in 1,800 m population. Chi-square values showed that only the 700 m population is not in Hardy-Weinberg equilibrium for the IDHP-A* locus, while for the IDHP-B* locus, no population is. Homogeneity Chi² test indicated that the populations are significantly different in their A and B phenotype frequencies. Wright's FST mean value (0.036 and 0.32, IDHP-A* and IDHP-B*, respectively) was 0.178 for the three altitude populations which means that 82% of total genetic diversity was found among individuals of each one of the populations. Stability at environmental temperatures (16º to 21ºC), and apparent Km and Vmax values of each A-phenotype skeletal muscle crude extract suggest different roles of A-isoforms during the increased lipogenesis that occurs in fish at low temperatures.

Observations of the feeding behavior of Cirriformia filigera (Delle Chiaje, 1825) (Annelida: Polychaeta) from the intertidal zone of São Francisco and Engenho D'água beaches (São Sebastião, State of São Paulo) were made in the laboratory. This species, like other cirratulids, is a deposit feeder, feeding mainly on sediment surface with the aid of its grooved and ciliated palps, which are used to capture food particles. The worm lies just beneath the substrate surface in a J-shaped tube. When feeding, it extends up to 4 palps over the sediment surface, capturing food particles which pass down the groove of each palp directly to the mouth. Only fine sand grains are ingested. The worm frequently extends 4 branchial filaments into the overlying water for aeration. When it moves with the prostomium sideways, it collects and transports sand grains that pass backwards along its ventral region until reaching the middle part of its body. Next, the parapodia and palps move the sand grains to the dorsal posterior end of the animal, covering this area with sand. Some sand grains are also ingested as the worm moves.

A comparison between two studies on diel vertical migration of two cyclopoid copepod species, in Lake Monte Alegre, undertaken in 1985/86 and 1999, revealed a change in their migratory behavior. In summer, during a period of marked stratification with low dissolved oxygen near the bottom, the organisms avoided the deepest layers, and migration was nocturnal or undetectable, in both periods. On other occasions, with partial or total circulation in the lake, a weak twilight migration of copepodites and adults in 1985 was replaced by the reverse in 1999. Differences were found among stages, with the weakest or undetectable migration being observed for nauplii. The migratory pattern change for copepodites and adults might be related with a recent predation pressure increase by Chaoborus larvae on copepods, after the virtual disappearance of their main cladoceran prey.

Recently, the hypothesis that the geographic distribution of species could be influenced by the shape of the domain edges, the so-called Mid-Domain Effect (MDE), has been included as one of the five credible hypotheses for explaining spatial gradients in species richness, despite all the unsuccessful current attempts to prove empirically the validity of MDE. We used data on spatial worldwide distributions of Falconiformes to evaluate the validity of MDE assumptions, incorporated into two different sorts of null models at a global level and separately across five domains/landmasses. Species richness values predicted by the null models of the MDE and those values predicted by Net Primary Productivity, a surrogate variable expressing the effect of available energy, were compared in order to evaluate which hypothesis better predicts the observed values. Our tests showed that MDE continues to lack empirical support, regardless of its current acceptability, and so, does not deserve to be classified as one possible explanation of species richness gradients.

This study evaluated the functional response of the predator Cosmoclopius nigroannulatus on first instar nymphae of Spartocera dentiventris, both species associated with Nicotina tabacum. The experiment was carried out in laboratory conditions: 27 ± 1ºC; 80 ± 5%, RH; 12 h, photophase. Ten newly emerged adults of each sex of C. nigroannulatus were used in each of five densities (5, 15, 25, 35, and 45 individuals) of S. dentiventris nymphae. The predators were observed every 24 h for five days, when the number of dead and/or consumed nymphae was recorded. The results showed a positive correlation between the number of ingested nymphae and the increase in prey density. Females ingested more nymphae than the males. The estimated handling time per prey (Th) was higher in males (3.07 h) than in females (1.93 h), with total handling time (Th x Na) increased with density. Other components of the functional response, such as attack rate (a'), searching time (Ts), and search efficiency (E) showed, in neither males nor females, a negative correlation regarding density. The results indicated a higher predatory efficiency in the females. The components of the functional response fitted significantly the randomic model of the Holling discs equation (Na = N {1 - exp[- a'(T - ThNa)]}), evidencing a functional response of type II.

The purpose of this work was to evaluate biochemical and serological methods to characterize and identify Candida species from the oral cavity. The strains used were five Candida species previously identified: C. albicans, C. guilliermondii, C. parapsilosis, C. krusei, C. tropicalis, and Kluyveromyces marxianus, as a negative control. The analyses were conducted through the SDS-PAGE associated with statistical analysis using software, chromogenic medium, and CHROMagar Candida (CA), as a differential medium for the isolation and presumptive identification of clinically important yeasts and an enzyme-linked immunoabsorbent assay (ELISA), using antisera produced against antigens from two C. albicans strains. This method enabled the screening of the three Candida species: C. albicans, C. tropicalis, and C. Krusei, with 100% of specificity. The ELISA using purified immunoglobulin G showed a high level of cross-reaction against protein extracts of Candida species. The SDS-PAGE method allowed the clustering of species-specific isolates using the Simple Matching coefficient, S SM = 1.0. The protein profile analysis by SDS-PAGE increases what is known about the taxonomic relationships among oral yeasts. This methodology showed good reproducibility and allows collection of useful information for numerical analysis on information relevant to clinical application, and epidemiological and systematical studies.

Populations of Anopheles triannulatus from Macapá (AP), Aripuanã (MT), Ji-Paraná (RO), and Manaus-Janauari Lake (AM) were studied using 16 enzymatic loci. The results of the isozyme analysis showed that the population of Macapá presented higher polymorphism (56.3%). The lowest variability was observed in the population of Manaus (p = 25.0; Ho = 0.077 ± 0.046). The results of Wright's F statistics showed unbalance due to excess of homozygotes (Fis > Fst), denoting a certain intrapopulational differentiation. Although the populations are genetically very close (D = 0.003 - 0.052), the dendrogram separates the populations in two groups: Macapá separated from that of Manaus, Ji-Paraná, and Aripuanã. This result may suggest a reduction in the genic flow, which possibly had some influence in the substructuration of the populations.

The fish assemblage in a mangrove tidal creek was studied in monthly collections between August 1998 and July 1999 in the quadrature low tide and high tide, using a fyke net of 30 m x 1.5 m and meshes of 8 and 10 mm. Simultaneously with the biological collections, temperature, salinity, pH, water transparency, and current speed data were obtained. The collections resulted in the capture of 36,873 fish representing 22 families and 52 species. Immature individuals abounded (63.8%), and among the adult specimens there was a larger number of females. The species Anchoa parva, Harengula clupeola, Genidens genidens, and Bairdiella ronchus, contributed to 84.9% of the total capture of fish, however the contribution in mass was of 55.2%, indicating a predominance of small individuals. A smaller number of fish and species seem to occupy the area in the period between August and December, in comparison to the period between February and July, when the larger aggregations appear, mainly of the species Anchoa parva, Harengula clupeola, Opisthonema oglinum, Genidens genidens, Diapterus rhombeus, and Bairdiella ronchus. The environmental factors, pH, water transparency, and rainfall seem to have an influence in the structure of the observed biological patterns.

Information on the ecology of lizard species from the Brazilian Atlantic Forest is scarce and almost nothing is known about the ecology of lizards of the genus Enyalius. In this study, we provide information about some aspects of the natural history of E. brasiliensis from an area of Atlantic Forest in Ilha Grande, RJ. Enyalius brasiliensis (N = 15) feeds mainly on arthropods. The most frequent food items were insect larvae, orthopterans, and ants; in terms of volume, larvae and termites were the most important food items; ants and termites were the most numerous prey categories. Two females were reproductive (one had 10 and the other, five vitellogenic follicles); the smallest measured 92.4 mm in SVL. Seven lizards were found on forest leaf litter. The other microhabitats used were vines, fallen logs, branches, and a crevice on a slope.

Dinoponera quadriceps is a queenless neotropical ponerinae ant. Nest spacing and abundance were investigated in a remnant of the Atlantic forest in Northeast Brazil. Males were captured with a light trap between August 1994 and July 1996. Nest density varied from 15 to 40 ha-1. An overdispersion of nests suggests that the intraspecific competition may be an important factor regulating their spatial arrangement. Territory size was correlated with worker population size of the colonies. The nests had up to 16 chambers, with variations in their architecture closely related to habitat diversification. Populations varied from 12 to 97 adult workers per nest, with a mean density of 1,618 workers ha-1 and a live biomass of 461 g ha-1 (n = 13 nests). Males swarm continually throughout almost all months of the year, suggesting that production and swarming are more influenced by mechanisms that regulate the sexual activity of workers than by climatic factors.

Two wild groups of Callithrix penicillata, the Black Pincelled Marmoset, were observed from January to September 1998, in two areas, one an area of dense scrub savanna vegetation (cerrado) and the other, a semidecidual woodland (cerradão), both within the boundaries of the Ecological Reserve of IBGE (Brazilian Institute of Geography and Statistics), in an environmentally protected area, the APA (Portuguese abbreviation for "environmental protected area") Gama/Cabeça-de-Veado, Brasília, DF. The behavioral data collected during the rainy (January 15 to April 15) and dry season (June 1 to September 15) were compared. Because of the proximity to the Reserve facilities, the group from the dense scrub savanna vegetation (CD) was submitted to antropic impacts different from the group in the semidecidual woodland (CE), which was using as territory an area that had been suffering from man-made fires every two years as part of a long-term experimental project on fire impacts. The behavioral data was quantified by instantaneous cross-section ("scan sampling") every ten minutes with records of locomotion, rest, foraging for insects, use of exudate, and feeding. During the whole year, the greatest percentage of time spent by CE and CD was in foraging for insects, with 44% and 39%, respectively. It was evident when comparing the data for the two seasons that, for both groups, foraging for insects was more intense during the dry season, possibly to complement the shortage of food, and locomotion increased during the rainy season. The greater the availability and distribution of fruit in the areas, the greater the locomotion of the groups to obtain these resources. None of the other behavioral patterns, including the use of exudates, presented significant differences between the two seasons. Both groups foraged more frequently during the dry season and locomoted more during the rainy one.

The relationship between habitats and the ichthyofauna composition in the Parque Nacional das Emas (PNE) and adjacent areas (the Araguaia and Sucuriú rivers) are provided and could be applied in determining the Park's future zoning. Samples of the ichthyofauna and limnological parameters were obtained during both dry (September 1999) and wet (December 1999) seasons. Ichthyofauna collections resulted in the capture of 4,740 specimens of 22 species. The most abundant species in the Araguaia River during the two sampling seasons were Astyanax sp. 2 and Hasemania sp. In the Sucuriú River and PNE, Astyanax scabripinnis cf. paranae and Hoplias aff. malabaricus were the most frequent species. The largest number of species and diversity index were recorded for the Araguaia River. However, sound management policies require more detailed studies on the fish communities of the Cerrado biome.

Total sequence phylogenies have low information content. Ordinary misconceptions are that character quality can be ignored and that relying on computer algorithms is enough. Despite widespread preference for a posteriori methods of character evaluation, a priori methods are necessary to produce transformation series that are independent of tree topologies. We propose a stepwise qualitative method for analyzing protein sequences. Informative codons are selected, alternative amino acid transformation series are analyzed, and most parsimonious transformations are hypothesized. We conduct four phylogenetic analyses of philodryanine snakes. The tree based on all nucleotides produces least resolution. Trees based on the exclusion of third positions, on an asymmetric step matrix, and on our protocol, produce similar results. Our method eliminates noise by hypothesizing explicit transformation series for each informative protein-coding amino acid. This approaches qualitative methods for morphological data, in which only characters successfully interpreted in a phylogenetic context are used in cladistic analyses. The method allows utilizing character information contained in the original sequence alignment and, therefore, has higher resolution in inferring a phylogenetic tree than some traditional methods (such as distance methods).

Eighty-nine specimens of Selene setapinnis (Mitchill, 1815) collected from the coastal zone of the State of Rio de Janeiro (21-23ºS, 41-45ºW and 23º05'S, 44º30'W), Brazil, from August 2001 to May 2002, were necropsied to study their metazoan parasites. Eighty-one (91%) specimens of S. setapinnis were parasitized by one or more metazoan species. Twenty-one species of parasites were collected: 8 digeneans, 3 monogeneans, 2 cestodes, 5 nematodes, and 3 copepods. The endoparasites (digeneans, cestodes, and nematodes) were 74.1% of total number of parasite specimens collected. The monogenean Pseudomazocraes selene (Hargis, 1957) was the most dominant species with the highest prevalence in the parasite community of S. setapinnis. The metazoan parasites of this host species showed the typical aggregated pattern of distribution. Only one parasite species (Acanthocolpoides pauloi Travassos, Freitas & Buhrnheim, 1955) showed positive correlation between the host total length and parasite abundance in S. setapinnis. Caligus robustus Bassett-Smith, 1898, P. selene, and Terranova sp. demonstrated positive correlation between the host total length and prevalence. Larvae of Terranova sp. showed influence of the host sex on its prevalence. A pair of ectoparasite species, P. selene-C. robustus, exhibited positive covariation between their abundances. Two pairs of endoparasite species, L. microstomum-P. merus and A. pauloi-P. merus showed significant covariation among their abundances; and the pair Terranova sp.-Raphidascaris sp. had positive co-ocorrence and covariation in the infracommunities of S. setapinnis. Like the parasite communities of the other carangid fishes from Rio de Janeiro, the parasite community of S. setapinnis is apparently only a slightly ordered species complex, characterized by dominance of endoparasite species.

The extinction of megafauna at the end of Pleistocene has been traditionally explained by environmental changes or overexploitation by human hunting (overkill). Despite difficulties in choosing between these alternative (and not mutually exclusive) scenarios, the plausibility of the overkill hypothesis can be established by ecological models of predator-prey interactions. In this paper, I have developed a macroecological model for the overkill hypothesis, in which prey population dynamic parameters, including abundance, geographic extent, and food supply for hunters, were derived from empirical allometric relationships with body mass. The last output correctly predicts the final destiny (survival or extinction) for 73% of the species considered, a value only slightly smaller than those obtained by more complex models based on detailed archaeological and ecological data for each species. This illustrates the high selectivity of Pleistocene extinction in relation to body mass and confers more plausibility on the overkill scenario.