Estimating colonies of Plebeia droryana (Friese, 1900) (Hymenoptera, Apidae, Meliponini): adults, brood and nest structure

Estimate of stingless bee colonies including nest structures and quantitative brood and adult individuals are scarce. Here, we describe a new approach to estimate colonial parameters from nest structure, adults and brood. We used five colonies of Plebeia droryana (Friese, 1900) to evaluate colony size and weight of adult and brood. Nest architecture in P. droryana is similar to the species of the same genus but differ to the other stingless bees. In this species, we counted a total of 9 to 12 brood combs and a total of 19 to 25 food pots in the nests. The number of individuals in the colonies is considered small and our estimate was based on individual and group weight. Our study approach may contribute to further detailed studies of the species nest and considering the stingless bees to the pollination of agricultural crops and native flora of tropical regions, it is important to add information about the biology of P. droryana

The acceptance rate of young wasps by alien colonies depends on colony developmental stages in the swarm-founding wasp, Polybia paulista von ihering (Hymenoptera: Vespidae)

In social insects, newly emerged individuals learn the colony-specific chemical label from their natal comb shortly after their emergence. These labels help to identify each individual's colony of origin and are used as a recognition template against which individuals can discriminate nestmates from non-nestmates. Our previous studies with Polybia paulista von Ihering support this general pattern, and the acceptance rate of young female and male wasps decreased as a function of their age. Our study also showed in P. paulista that more than 90% of newly emerged female wasps might be accepted by conspecific unrelated colonies. However, it has not been investigated whether the acceptance rate of newly emerged female wasps depends on colony developmental stage of recipient colonies. We introduced newly emerged female wasps of P. paulista into different colony developmental stags of recipient colonies, i.e., worker-producing and male-producing colonies. We found that the acceptance rate of newly emerged female wasps by alien colonies was pretty lower by male-producing colonies than worker-producing colonies. This is the first study to show that the acceptance rate of young female wasps depends on stages of recipient colonies

A New Species of the Neotropical Social Swarming-Wasp Chartergellus Bequaert (Hymenoptera: Vespidae: Epiponini).

Abstract- A new species of Chartergellus, collected in Acre State, is described and comparative remarks are given

Presence of Strepsiptera Parasites in the Independent-founding Wasp, Polistes satan

Although the paper wasp genus, Polistes, has been examined extensively, little is known about the occurrence of parasitism in this group. We detected the obligate parasitic insect group, Strepsiptera in the gaster of Polistes satan Bequaert adult females. By dissecting 161 adult females from 24 colonies, we identified a total of four stylopized wasps in three colonies during the wet season.

Description of a new species of Metapolybia, a Neotropical genus of social wasps, from the Amazon Forest.

A new species of Metapolybia, which had been included erroneously among the paratypes of M. acincta by Richards (1978) is described

Diversity and Temporal Variation in the Orchid Bee Community (Hymenoptera: Apidae) of a Remnant of a Neotropical Seasonal Semi-deciduous Forest

Multiple biotic and abiotic variables control the composition, diversity, and temporal fluctuations of insect communities. In particular, the assembly of bee communities is strongly influenced by climatic factors as well as variation in food resource availability, which in turn also fluctuates in response to the same factors. The goal of the present study was to investigate the species composition, the species richness and the abundance of the euglossine bees in a remnant of the seasonal semi-deciduous forest of northeastern São Paulo state, and evaluate the temporal variation in those parameters over time. From January to December 1990, males of euglossine bees were sampled using three aromatic baits. We collected 643 males belonging to 12 species and three genera. Euglossa imperialis Cockerell was the most abundant species, followed by Eulaema nigrita Lepeletier and Euglossa melanotricha Moure. The composition and species richness showed temporal variation throughout the year, with the highest values being observed during the rainiest months. Such variations occurred by the presence of males from six species which were sampled only during the rainiest months. Of the five most abundant species, Eg. imperialis and Eg. melanotricha were the only species sampled throughout the year. Only El. nigrita and Eg. melanotricha, had the monthly abundance of males correlated with precipitation. Based on the assumption that male euglossine capture rates reflect actual abundance at the sampled habitats, we believe that Eg. imperialis, usually represented by few male in other studies, has a population very well established in the habitat here studied

Nest thermoregulation in Polybia scutellaris (White) (Hymenoptera: Vespidae)

Polybia scutellaris (White) builds large nests characterized by numerous spiny projections on the surface. In order to determine whether or not the nest temperature is maintained because of homeothermic conditions of the nest individuals or otherwise, we investigated the thermal conditions within the nests built by P. scutellaris. We measured the temperature within active and abandoned nests. The temperature in the active nest was almost stable at 27°C during data collection, whereas the temperature in the abandoned nest varied with changes in ambient temperature. These results suggest that nest temperature was maintained by the thermogenesis of the individuals of the colony. This is the first report of nest incubation caused by thermogenesis of species of Polybia wasps

Polymorphic Microsatellite Loci in the Independent-founding Wasp Polists versicolor (Hymenoptera: Vespidae)

Microsatellite primers developed for a given species are sometimes useful for another in the same genus, making possible to search for pre-existing suitable primers in the data banks such as GenBank. We examined whether existing primers developed for Polistes wasps could be used for the independent-founding wasp Polistes versicolor. We tested 50 microsatellite primers from three Polistes species and found that five microsatellite loci show polymorphism in size in P. versicolor. These five loci were highly polymorphic, having four to 10 alleles in P. versicolor with an expected heterozygosity of 0.530–0.836. These loci can be used to study parameters concerning genetic relatedness such as social interactions in colonies and genetic conflicts of interest among nestmate individuals

Neutral Sterols of Cephalic Glands of Stingless Bees and Their Correlation with Sterols from Pollen

Sterols are essential molecules in the membrane lipid composition and precursors of important sterol hormones that regulate many developmental processes. Insects are unable to synthesize sterols de novo and, thus, all phytophagous insects depend on an exogenous source of sterols for growth, development, and reproduction. The sterol requirements of social bees are not fully known due to the fact that there is no well-defined diet available throughout the year with regard to floral resources. Our study aimed to characterize the sterols present in pollen stored in Melipona marginata and Melipona scutellaris colonies, as well as evaluating their presence in the mandibular, hypopharyngeal, and cephalic salivary gland secretions. We analyzed the chemical composition of pollen stored in the colonies and the composition of the cephalic glands of workers in three adult functional phases (newly emerged, nurses, and foragers) by gas chromatography and mass spectrometry. The results showed that the pollen analyzed contained campesterol, stigmasterol, sitosterol, isofucosterol, lanosterol, and small amounts of cholesterol. The glands showed the same compounds found in the pollen analyzed, except lanosterol that was not found in M. scutellaris glands. Surprisingly, cholesterol was found in some glands with relative ratios greater than those found in pollen