Distribution of Resources Collected Among Individuals From Colonies of Mischocyttarus drewseni (Hymenoptera, Vespidae)

The aim of this study was to analyze the distribution pattern of the food collected among groups of individuals in Mischocyttarus drewseni colonies. This behavior is one of the first actions exhibited by the foragers when they arrive in the colonies. Regarding nectar and prey collection, 95.90% of the collected nectar was given to larvae, whereas 3.57% to dominant individuals and 95.94% of the collected prey were given to the larvae, 2.54% to the dominant members, while the remainder of both was given to the workers. Despite not being significant, it was possible to observe a difference in food distribution among larvae, with larger larvae receiving more food than others. When the forager returns to the nest with pulp, it adds this material to cells in 64.29% of the times. Males showed agitated behavior with the arrival of the foragers, and sometimes took the foraged material from them

The Social Wasp Fauna of a Riparian Forest in Southeastern Brazil (Hymenoptera, Vespidae)

An inventory of social wasps was made in a section of riparian forest along the Passa-Cinco River in Ipeúna, São Paulo, Brazil. Two active collecting methods (active collecting and point sampling using a liquid bait) and one passive method (baited PET bottle trap) were used. Thirty-one species belonging to eight genera were recorded; the most abundant were Agelaia vicina and Agelaia pallipes, species belonging to the tribe Epiponini which was dominant in the sample. In the State of São Paulo, a local richness greater than the one sampled in Ipeúna was only reported for Rio Claro city. Regarding sampling methods, active collecting obtained the greatest richness value and also presented the largest number of exclusive species to a given method; however, for the other methods as well, exclusive species were also obtained

Colony Defense Behavior of the Primitively Eusocial Wasp, Mischocyttarus cerberus is Related to Age

The colony defense behavior of the wasp Mischocyttarus cerberus Richards (Hymenoptera, Vespidae) was studied to verify whether there were different reactions of wasps of different ages and hierarchical positions during attacks of ants. Detailed nest mapping was first performed, then the wasps were marked and were divided in four distinct categories: queens, older workers, younger workers and males. Tests were made simulating attacks of ants in the nests. The main results showed that the M. cerberus behaviors against ant attacks is more related to the age of the wasps than to their hierarchical position. The oldest wasps (queens and older workers) defend the nest more than the younger workers and males, representing a form of temporal polyethism

Diversidade de vespas sociais (Hymenoptera, vespidae) na Mata Atlântica do litoral norte do estado de São Paulo

A Mata Atlântica é um ecossistema muito relevante para a biologia da conservação e possui uma das maiores diversidades de espécies do continente, inclusive a de vespas sociais. Este grupo de insetos, que no Brasil está representado pelos Polistinae, causa grandes impactos nos ecossistemas, já que as vespas são importantes predadoras e coletoras de néctar. Tendo em vista que o inventário das espécies de uma área é o ponto inicial para a sua preservação, o objetivo do estudo foi efetuar um levantamento da diversidade de vespas sociais da Mata Atlântica da Serra do Mar do litoral norte do estado de São Paulo, enfatizando a importância desse grupo para avaliações de impacto ambiental e de efeitos de fragmentação florestal da região. Além disso, foi possível comparar a eficiência das metodologias utilizadas, verificando se ocorre preferência das vespas pelo conteúdo das armadilhas. As coletas foram realizadas na Fazenda Angelim Rainforest de maio de 2007 a maio de 2008, utilizando armadilhas atrativas de garrafa PET e coleta ativa. Foram encontradas 21 espécies pertencentes a oito gêneros e, dentre elas, algumas são raras na região sudeste do país, como Mischocyttarus parallelogrammus e Polybia catillifex. As espécies mais freqüentes foram Agelaia angulata (64,31%), A. sp. prox. centralis (10,08%) e Angiopolybia pallens (8,49%). Observou-se correlação entre a riqueza das espécies e a umidade relativa do ar. Analisando os distintos ambientes, verificou-se maior riqueza, abundância e índice de diversidade de Margalef na área antropizada (A=793, R=14, DMg=4,4839, H’=1,08), mas a maior diversidade obtida pelo índice de Shannon-Wiener foi na área de mata fechada (A=174, R=8, DMg=3,1242, H’=1,17). As armadilhas com atrativo glucídico obtiveram maior riqueza, igual a 16 espécies ou 76,19% da riqueza total coletada. As armadilhas...The Atlantic Rain Forest is very relevant for conservation biology and has one of the greatest biodiversity in the continent, including social wasps diversity. This group of insects, which in Brazil is represented by Polistinae, causes major impacts on ecosystems, because the wasps are important predators and collectors of nectar. Bearing in mind that the inventory of species in an area is the starting point for its preservation, the goal of this study was to perform a survey of the social wasps diversity of the Atlantic Forest on the north coast of São Paulo State, emphasizing the importance of this group for environmental impact assessments and the effects of forest fragmentation in the region. Furthermore, it was possible to compare the efficiency of the methodologies, verifying if there is a preference of the wasps for the contents of the traps. The collections were made in Fazenda Angelim Rainforest from May 2007 to May 2008, using attractive PET bottles traps and active searching. We found 21 species belonging to eight genera and among them; some are rare in the southeast region of the country, such as Mischocyttarus parallelogrammus and Polybia catillifex. The most frequent species were Agelaia angulata (64.31%), A. sp. prox. centralis (10.08%) and Angiopolybia pallens (8.49%). Correlation was observed between species richness and relative air humidity. When analyzing the different environments, it was possible to verify a greater richness, abundance and Margalef diversity index in the anthropic area (A= 793, R= 14, DMg= 4.4839, H= 1.08), but the greatest diversity obtained by Shannon-Wiener index was in the area of dense vegetation (A= 174, R= 8, DMg= 3.1242, H'= 1.17). The traps with glucidic attractive obtained greater richness, equal to 16 species or 76.19% of total richness collected. Traps with protein content were the least effective (six species, 28.57% of total richness)... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Biologia e ecologia comportamental da vespa eussocial primitiva Mischocyttarus (Megacanthopus) parallelogrammus (Hymenoptera, Vespidae)

The social wasps are represented in Brazil by Polistinae, which is arranged in 21 genera divided among the tribes Mischocyttarini, Polistini and Epiponini. The Mischocyttarini tribe represents the largest genus of social wasps, Mischocyttarus, with 245 species distributed in nine subgenres. The species of Mischocyttarus are considered primitive eusocial, of independent foundation and without morphological caste differentiation. The studied species, Mischocyttarus (Megacanthopus) parallelogrammus, is endemic to Brazil, being the objective of this study to conduct a preliminary study involving features of the biology of M. parallelogrammus, in order to cooperate with investigations into the evolution of the eusociality in wasps, by analyzing aspects of the colony cycle, the nest architecture, the labor division, the foraging activity, the dominance hierarchy and the chemical and visual communication of this species. Like in other species, M. parallelogrammus presents foundations and abandonments throughout the year. Abandonment rates are probably related to the wide variety of observed natural enemies, with only 13.89% of the total colonies studied reaching the stage of natural decline. Of the remaining colonies observed, 31.94% were abandoned for unknown reasons, 27.78% were abandoned by the occurrence of parasites or parasitoids, 12.50% were contaminated by fungi and 12.50% were predated. The foundation of the colonies by haplometrosis was predominant (81.94%), even with the foundations of females by association representing greater success. The interval of development of immature M. parallelogrammus appeared greater than other species of the genus, with the average total development time of immatures being 85.20 days. The founders of M. parallelogrammus had an average lifespan of 82.71 ± 53.32 days, 95.81 ± 62.25 days for subordinates and 191.86 ± 91.19 days for dominants. Nests of M. parallelogrammus are attached by a short peduncle...As vespas sociais do país estão representadas pelos Polistinae que abrangem 21 gêneros subdivididos nas tribos Mischocyttarini, Polistini e Epiponini. A tribo Mischocyttarini é formada pelo maior gênero de vespídeos sociais, Mischocyttarus, com 245 espécies distribuídas em nove subgêneros. As espécies de Mischocyttarus são consideradas eussociais primitivas, com fundação independente e sem diferenciação morfológica de castas. A espécie estudada, Mischocyttarus (Megacanthopus) parallelogrammus é endêmica do Brasil, sendo que objetivo deste trabalho foi realizar um primeiro estudo envolvendo características da biologia de M. parallelogrammus, de forma a colaborar com as investigações sobre a evolução da eussocialidade nas vespas, analisando aspectos do ciclo colonial, da arquitetura do ninho, da divisão de tarefas, da atividade forrageadora, da hierarquia de dominância e da comunicação química e visual desta espécie. No total foram estudadas 96 colônias de março de 2010 a novembro de 2013. Assim como em outras espécies, M. parallelogrammus apresenta fundações e abandonos durante todo o ano. Os índices de abandono provavelmente estão relacionados com a grande variedade de inimigos naturais observados, sendo que apenas 13,89% do total das colônias estudadas atingiram o estágio de declínio natural. Do restante das colônias observadas, 31,94% foram abandonadas por motivos desconhecidos, 27,78% foram abandonados pela ocorrência de parasitas ou parasitóides, 12,50% foram contaminadas por fungos e 12,50% foram predadas. A fundação das colônias por haplometrose foi predominante (81,94%), mesmo as fundações por associação de fêmeas representando um maior sucesso. O intervalo de desenvolvimento dos imaturos de M. parallelogrammus foi maior que de outras espécies do gênero, sendo que o tempo médio total de desenvolvimento dos imaturos foi de 85,20 dias. As fundadoras de M. parallelogrammus apresentaram um...Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Nest defense behavior against ant attacks in post-emergent colonies of wasp Mischocyttarus cerberus (Hymenoptera, Vespidae)

The primitive eusocial wasp Mischocyttarus cerberus forms colonies of independent foundation, without morphological differentiation among castes. Ants are natural enemies of the social wasps and defending the wasps' nests involves chemical and active defense strategies. The aims of this work were to verify the kind of defense the wasps use most frequently in post-emergent colonies of M. cerberus. We also observed whether the nest was abandoned during the ant attack and whether any relationship existed between the forms that colony defense took and the number of adults, the number of cells, and the number of immature wasps. The study was carried out on the campus of Universidade Estadual Paulista of Rio Claro, São Paulo, Brazil. The 23 nests under study were mapped weekly, and 68 bioassays were performed by simulating ant attacks against the nests. The results showed that wasps used both active and chemical strategies for nest defense, and the PCA analysis showed that the aggressive behaviors of biting the ant, wings vibrating, gaster hitting, and abdomen pumping were the dominant terms; the PCA correlation values were 2.70, 2.54, 1.64, and 1.63, respectively. The colonies in pre- and post-male substages with few immature wasps and the nests in post-male substage with one adult were more correlated with the nonaggressive behaviors of hiding, staying immobile, and flying; their PCA correlation values were 3.12, 2.56, and 1.77, respectively. These results show that the number of immature wasps is an important factor in the kind and in the intensity of the defense behavior against ant attacks.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Male behavior of Mischocyttarus cerberus (Hymenoptera, Vespidae) during attacks on the nest by ants

The objectives of the present study were to verify if the males of the wasp Mischocyttarus cerberus participate in defense of the nest as they react to attack by ants, and to observe if they use chemical defense. First, wasps were stimulated with an empty pair of tweezers and a second stimulation was done with a pair of tweezers containing an ant, Camponotus crassus. The behaviors of the wasps were recorded and analyzed. The males can participate in defense of the nest, presenting some aggressive behaviors, even so, most of the time they ignore the stimulation, hide behind the nest and stay immobile

Nest defense behavior against the attack of ants in colonies of pre-emergent Mischocyttarus cerberus (hymenoptera, vespidae)

The study was carried out at the UNESP Rio Claro campus (SP), where biotests consisting of simulated ant attacks were performed in colonies of Mischocyttarus cerberus. The behaviors of the wasps were recorded with a camcorder, for further analysis. This analysis was done using the Mann-Whitney U test and the Principal Component Analysis. In the pre-emergence development stage, colonies with a single foundress defend the nest only after the first larvae appear. When there are only eggs in the nest, the wasp abandons the nest. Before leaving, the wasp rubs its gaster against the nest, releasing the ant repellent secretion. When the nest contains larvae or larvae and pupae, the foundress defends the colony, vibrating its wings, pumping her abdomen and biting the ant