952 resultados para Conspecific Brood Parasitism


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The known diversity of dart-poison frog species has grown from 70 in the 1960s to 247 at present, with no sign that the discovery of new species will wane in the foreseeable future. Although this growth in knowledge of the diversity of this group has been accompanied by detailed investigations of many aspects of the biology of dendrobatids, their phylogenetic relationships remain poorly understood. This study was designed to test hypotheses of dendrobatid diversification by combining new and prior genotypic and phenotypic evidence in a total evidence analysis. DNA sequences were sampled for five mitochondrial and six nuclear loci (approximately 6,100 base pairs [bp]; x=3,740 bp per terminal; total dataset composed of approximately 1.55 million bp), and 174 phenotypic characters were scored from adult and larval morphology, alkaloid profiles, and behavior. These data were combined with relevant published DNA sequences. Ingroup sampling targeted several previously unsampled species, including Aromobates nocturnus, which was hypothesized previously to be the sister of all other dendrobatids. Undescribed and problematic species were sampled from multiple localities when possible. The final dataset consisted of 414 terminals: 367 ingroup terminals of 156 species and 47 outgroup terminals of 46 species. Direct optimization parsimony analysis of the equally weighted evidence resulted in 25,872 optimal trees. Forty nodes collapse in the strict consensus, with all conflict restricted to conspecific terminals. Dendrobatids were recovered as monophyletic, and their sister group consisted of Crossodactylus, Hylodes, and Megaelosia, recognized herein as Hylodidae. Among outgroup taxa, Centrolenidae was found to be the sister group of all athesphatanurans except Hylidae, Leptodactyidae was polyphyletic, Thoropa was nested within Cycloramphidae, and Ceratophryinae was paraphyletic with respect to Telmatobiinae. Among dendrobatids, the monophyly and content of Mannophryne and Phyllobates were corroborated. Aromobates nocturnus and Colostethus saltuensis were found to be nested within Nephelobates, and Minyobates was paraphyletic and nested within Dendrobates. Colostethus was shown to be rampantly nonmonophyletic, with most species falling into two unrelated cis- and trans-Andean clades. A morphologically and behaviorally diverse clade of median lingual process-possessing species was discovered. In light of these findings and the growth in knowledge of the diversity of this large clade over the past 40 years, we propose a new, monophyletic taxonomy for dendrobatids, recognizing the inclusive clade as a superfamily (Dendrobatoidea) composed of two families (one of which is new), six subfamilies (three new), and 16 genera (four new). Although poisonous frogs did not form a monophyletic group, the three poisonous lineages are all confined to the revised family Dendrobatidae, in keeping with the traditional application of this name. We also propose changes to achieve a monophyletic higher-level taxonomy for the athesphatanuran outgroup taxa. Analysis of character evolution revealed multiple origins of phytotelm-breeding, parental provisioning of nutritive oocytes for larval consumption (larval oophagy), and endotrophy. Available evidence indicates that transport of tadpoles on the dorsum of parent nurse frogs-a dendrobatid synapomorphy-is carried out primitively by male nurse frogs, with three independent origins of female transport and five independent origins of biparental transport. Reproductive amplexus is optimally explained as having been lost in the most recent common ancestor of Dendrobatoidea, with cephalic amplexus arising independently three times. © American Museum of Natural History 2006.

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The aim of the present study was to evaluate the frequency of rhabdiasid nematodes in recently captured Crotalus durissus terrificus snakes from São Paulo State, Brazil. Fifty snakes (34 males and 16 females) were studied and each one was evaluated for the presence of that nematode at the moment of receipt at the Institution and after 90 days of quarantine inside individual cages. Tracheopulmonary washes were examined. Snakes that died during quarantine underwent necropsy and lung examination. Analysis of the results obtained at the two evaluation times (0 and 90 days), in addition to the data obtained during necropsies, showed that 44% (18 males and 4 females) of the C. d. terrificus snakes were naturally infected by rhabdiasid nematodes. These data demonstrate the parasitism level in natural conditions and are important for the sanitary handling of these reptiles in captivity.

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This study examines some aspects of the basic biology of the worldwide distributed ant Tapinoma melanocepbalum Fabricius. The number of larval instars and the growth ratio between each instar are given. We used colonies containing only queens and workers, and later removed these queens in order to estimate the production of eggs and the duration of immature development of the worker caste. Measurements of larvae cephalic capsule widths revealed that workers of the ghost-ant have four larval instars from egg-hatching to adult. The mean growth rate for the species is 1.38, in accordance with Dyar's rule. The highest egg production was 5.3±2.2 eggs/day/queen and the analysis of these brood suggested the presence of two kinds of eggs inside the colony. The development of workers from egg to adult lasted 16-52 days with the embryonic development longer than larval, prepupal or pupal stages. Despite the slow egg-laying by queens, our findings also showed that colonies of T. melanocephalum grow faster than colonies of other tramp ants.

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The genus Paratrechina (Motschulsky) is composed of about 147 cosmopolitan ant species and subspecies, of which some were accidentally spread by commerce around the world, infesting houses and hospitals. In Brazil, two species are of remarkable economic importance: Paratrechina fulva (Mayr) and Paratrechina longicornis (Latreille). The present paper aims to report the following aspects on the biology of P. longicornis: number of larval instars, growth rates, duration and viability of the developmental stages and some observations on brood-care behaviour. Artificial colonies were kept under controlled temperature (25±2°C) and relative humidity (60±10%) conditions. To access the number of larval instars, we analyzed 1531 larvae fixed in Dietrich by measuring their maximum head capsule widths. We analysed ten artificial colonies daily to measure the developmental time and viability of immatures. We found P. longicornis presented three larval instars and a mean growth ratio of 1.2988. Egg stage was found to last 16.1 ±0.1 days, with a viability of 24.6%; larval stages were found to last 18.3±0.1 days, with a viability of 33.3% and the pupal stage was found to last 12.3±0.1 days, with a viability of 65.3%.

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This paper reports the effect of mating delay on the queen Apis mellifera ovaries based on a light microscopy analysis. Soon after a queen emerges from the brood cell, oocytes start to differentiate in the ovaries, but if mating does not occur at the correct age (about 6 days after emergence) cell degeneration begins. Ovaries of 15-day-old virgin queens show extensive disorganization with cell death affecting all types of ovariole cells. Types of cell death and the possible causes are discussed.

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The objective of this study was to evaluate the occurrence of Drosophilidae and their parasitoids in coffee fruits in Cravinhos, SP, Brazil. The fruits were collected directly from the tree, and a portion was exposed under the canopy. Fifty-nine drosophilid pupae were collected in all, of which 31 adults (including two Ganaspis exemplars) emerged. The survival rate of all pupae was 49.2%. Thirty-five drosopholid pupae were obtained from the fruit trees, 24 of which later emerged, three different species: Zaprionus indianus Gupta, Drosophila nebulosa Sturtevant and D. simulans Sturtevant. From the fruits under the canopy of plants were obtained 24 pupae of four different species: Z. indianus, D. cardini Sturtevant, D. immigrans Sturtevant and D. willistoni Sturtevant. The emergence of two Ganaspis sp. (Hymenoptera: Figitidae) examples, with a parasitism rate of 8.3%, was also observed. Half of the drosophilids collected are introduced species and represented 79% of the adults emerged. Associations between Z. indianus, D. cardini, D. immigrans, D. nebulosa, D. simulans and D. willistoni and the coffee crop are reported herein.

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This study aimed to determine the effect of sucrose ester on the control of Varroa destructor mite infestation in Africanized honeybees. For the in vitro experiments, the product was tested in bees and mites at five concentrations obtained through dilution in water (T0: 100% distilled water; T1: 0.5%; T2: 1%; T3: 2%; T4: 5%; and T5: 10% sucrose ester).For the field studies, the experimental design was completely randomized, with four treatments and seven replicates, totaling 28 colonies, from which seven were the controls, seven were treated with 0.1% sucrose ester, seven with 0.2% sucrose ester, and seven hives with 0.5% sucrose ester diluted in water. In the in vitro study, the sucrose ester at 0.5% concentration caused mite and bee mortality. In the field tests, the product at 0.2% concentration reduced Varroa destructor infestation in Africanized honeybees and, therefore, may be used as a tool to control this pest. At 0.1, 0.2, and 0.5% concentrations, sucrose ester did not impair the establishment of open and capped brood areas, as well as stored food areas in the hive, suggesting it is not toxic to Africanized honeybees.

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The boll weevil (Anthonomus grandis Boheman, 1843) (Coleoptera: Curculionidae) is a pest that limits the production of cotton, especially in the North East of Brazil. The present study aimed to estimate the infestation index and natural mortality of boll weevil at Caraibas County, located in the semi-arid of the Southwest ofBahia. The experiment was performed using the cultivar BSR Aroeira, at Fazenda Lagoa Seca, in 2006. Weekly evaluations were performed, in five sampling areas 25m2, collecting blossoms fallen on the ground. The infestation was estimated by counting the oviposition punctures and /or the feeding on blossoms, and also by the presence of one of the phases of the boll weevil in the inside. Mortality factors were studied through the dissection of blossoms, estimating predation, parasitism, dissection and disease. The results obtained allowed to conclude that the boll weevil determines high infestation levels in the region. Parasitism, dissection and predation, following this order, determine high rates of real mortality of the pest. Catolaccus grandis Burks, 1954 (Hymenoptera: Pteromalidae) and Bracon sp.(Hymenoptera: Braconidae) are parasitoids of boll weevil reported in sothwestern Bahia, being the first one the predominant species. © 2009, Sociedad Venezolana de Entomología.

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The goal was to investigate the influence of natural products such as lemongrass (Cymbopogon citratus), dried avocado leaves (Persea americana), coffee husk (Coffea arabica) and castor bean (Ricinus communis) in the defense of Apis mellifera, as well the effect of these products on the population development of the beehive. Defensive behavior was evaluated by time of first sting (TFS) and number of stingers (NS), and population development, by open brood area and operculated brood. It was observed that the treatment with smoke + seven castor beans presented significant increase in the TFS, for treatment without and with smoke. Regarding NS, it was verified that the treatments with smoke + seven castor bean and smoke + 20% coffee husk were different from the treatment without and with smoke. The other treatments did not differ significantly with respect to the use of smoke or its absence. The application of coffee husk and castor bean did not interfere in the development of the population, suggesting that these compounds were not toxic. It can be concluded that the use of castor bean and coffee husk in smoke may represent an important tool for the reduction of defensiveness, without promoting toxicity for A. mellifera.

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Considerable losses during apple fruit storage occur due to microbiological diseases, mainly caused by Penicillium expansum, which in addition to fruit pulp deterioration produces patulin, a mycotoxin with carcinogenic and teratogenic activity. Biological control of post-harvest disease by antagonist yeasts focused on killer toxins is an appreciable alternative to the chemical fungicides, due to the low possibility of toxic residues demonstrated during fermentative processes. Twenty out of 44 yeasts (16 isolated from fruits, 10 from corn silage and 18 from laboratory anthill), showed antagonism against spores of P. expansum. The assay in solid medium pointed the strongest nutrient competition antagonism by D. hansenii strain C1 (31 mm inhibition diameter), while D. hansenii strain C7 (15 mm) showed higher antibiosis and parasitism pattern. In the following step the extracellular activity was tested performing the assay with culture supernatant in Yeast Medium agar, where C. guilliermondii P3 was more effective against conidia germination (inhibition rate of 58.15%) while P. ohmeri showed better inhibition on micelial growth (66.17%). The antibiosis showed by both yeasts could suggest probable mechanism associated with killer phenomenon, once both strains were killer positive against sensitive reference strains (S. cerevisiae NCYC 1006 and P. kluyveri CAY-15). In order to enhance the production of antifungal substance, these yeasts were cultivated with P. expansum, but the difference between culture supernatant obtained from yeasts cultivated alone and with mould was not significant (P > 0.05). The results demonstrated that the yeasts application constitute a promising tool, enhancing the biological control of P. expansum in post-harvest diseases of apple fruit.

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Four colonies of the ant Pachycondyla striata were used to analyze the specie behavioral repertoire. Forty-six behavioral acts were recorded in laboratory. Here, we present the record the division of labor between the castes and the temporal polyethism of monomorphic workers. The queens carried out many of the behavioral traits recorded in this work however; they performed them less frequently compared to the worker. The workers activity involved chasing and feeding on fresh insects and usingthem to nourish larvae besides laying eggs in the C-posture, an activity also performed by queens, which is similar to that of wasps of the subfamily Stenogastrinae. The young workers were involved in activities of brood care, sexuate care, and nest maintenance, and the older workers were involved in defense, exploration, and foraging. © 2012 Adolfo da Silva-Melo and Edilberto Giannotti.

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We present a detailed description of the predatory behavior of the beetle Canthon virens Mannerheim, 1829, on the leafcutter ant Atta sp. We observed 51 acts of predation, which were also recorded on film and subjected to behavioral analysis. Canthon virens exhibited 28 behaviors while predating upon Atta sp. queens. Adult beetles search for queens while flying in a zigzag pattern, 15 to 20cm above the ground. After catching a queen, the predator stands on its back and starts cutting the queen cervix. Once the prey is decapitated, the predator rolls it until an insurmountable obstacle is reached. The distance from the site of predation to the obstacle can vary widely and is unpredictable. The beetle rolling the queen also buries it in a very peculiar way: first, it digs a small hole and pulls the queen inside, while another beetle is attached to the prey. The burial process takes many hours (up to 12) and may depend on the hardness of the soil and the presence of obstacles. In general, one or two beetles are found in a chamber with the queen after it is buried. They make the brood balls, which serve as food for the offspring. This study contributes to the knowledge of the predatory behavior of Canthon virens, a predator poorly studied in Brazil and widespread in the country. Copyright © 2012 Luiz Carlos Forti et al.

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The determination of mean intensity of parasitism for colony-forming sessile protozoan such as Epistylis has been a great problem in parasitological studies. Some alternatives have been proposed by researchers for laboratory and field conditions. This study describes the criteria to establish the parasitic intensity score for epistylidid infestation in fish. Parasite distribution and the host-parasite relationship in four species of Brazilian cultured catfish and their hybrids are discussed. The highest prevalence rates were found in the hybrid jundiara, Leiarius marmoratus male × Pseudoplatystoma reticulatum female (96.4 %), followed by jurupoca, Hemisorubim platyrhynchos (60 %), and the hybrid surubim, Pseudoplatystoma corruscans male × P. reticulatum female (52.7 %). Positive correlation between parasitic intensity score and the fish size, weight, and relative condition factor were also observed. These findings indicate that Epistylis infestation in Brazilian catfish is an emerging disease in cultured fish. © 2012 Springer-Verlag.

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In this study, we used data from both experiments and mathematical simulations to analyze the consequences of the interacting effects of intraguild predation (IGP), cannibalism and parasitism occurring in isolation and simultaneously in trophic interactions involving two blowfly species under shared parasitism. We conducted experiments to determine the short-term response of two blowfly species to these interactions with respect to their persistence. A mathematical model was employed to extend the results obtained from these experiments to the long-term consequences of these interactions for the persistence of the blowfly species. Our experimental results revealed that IGP attenuated the strength of the effects of cannibalism and parasitism between blowfly host species, increasing the probability of persistence of both populations. The simulations obtained from the mathematical model indicated that IGP is a key interaction for the long-term dynamics of this system. The presence of different species interacting in a tri-trophic system relaxed the severity of the effects of a particular interaction between two species, changing species abundances and promoting persistence through time. This pattern was related to indirect interactions with a third species, the parasitoid species included in this study. © 2012 The Society of Population Ecology and Springer Japan.