Rute Magalhães Brito

Alelle number and heterozigosity for microsatellite loci in different stingless bee species (Hymenoptera: Apidae, Meliponini)

In the present study we compare genetic characteristics (allele diversity and observed heterozygosity) of microsatellite loci, from three stingless bee species (Plebeia remota Holmberg, Partamona mulata Moure In Camargo and Partamona helleri Friese), amplified by using heterospecific primers originally designed for Melipona bicolor Lepeletier and Scaptotrigona postica Latreille. We analyzed 360 individuals of P. remota from 72 nests, 58 individuals of R. mulata from 58 nests, and 47 individuals of P. helleri from 47 nests. The three species studied showed low level of polymorphism for the loci amplified with primers derived from M. bicolor. However, for the loci amplified with primers derived from S. postica, only P. remota presented low level of polymorphism.

Cytogenetic data of Partamona peckolti (Hymenoptera, Apidae, Meliponini) by C banding and fluorochrome staining with DA/CMA3 and DA/DAPI

The stingless bees of the Partamona genus have been studied taxonomically, ecologically and behaviourally, but cytogenetic studies are still rare. The objective of this study was to obtain cytogenetic data to contribute to Partamona peckolti species characterization. Heterochromatin was localized in all chromosome pericentromeric regions but some blocks could be visualized on some large chromosomes arms. A large heterozygous DA-CMA3-positive band was observed on one large chromosome arm, but was completely absent when C banding was applied before fluorochrome staining, with only one small positive band being visualized. Sequential DA-CMA3-NOR staining of interphase nuclei provided coincident positive responses. This suggests that DA-CMA3-positive bands of P. peckolti correspond to nucleolar organizer regions, as previously confirmed for another Partamona species by FISH.

Characterization of microsatellite loci of Tetragonisca angustula (Hymenoptera, Apidae, Meliponini)

An enriched genomic library was constructed from Tetragonisca angustula, a stingless bee species widely distributed in Brazil. The library was screened using two simple-repeat oligonucleotide probes and 21 microsatellite primer pairs were designed flanking a selection of repeat sequences within positive clones. The polymorphism of the microsatellite loci was analyzed by screening a sample of 19 unrelated T. angustula workers. Fifteen out of 21 loci were shown to be polymorphic, with observed heterozygosity estimates ranging from 0.00 to 0.89. The primers were also successfully used to amplify microsatellite loci from other stingless bee species, Tetragonisca fiebrigi, Tetragonisca weyrauchi, Lestrimelitta maracaia and Schwarziana quadripunctata. The results from variability analyses suggest that the microsatellite loci isolated from T. angustula will be useful in further population studies for the species and also for other Meliponini.

Isolation and characterization of 15 microsatellite loci in the stingless bee Plebeia remota (Apidae: Meliponini)

The destruction of Brazilian natural habitats has reduced bee populations and negative impacts of native flora pollination have been noticed. This work describes the isolation and characterization of microsatellite loci and evaluates them as molecular markers to study genetic variability of the stingless bee Plebeia remota. A microsatellite enriched genomic library was constructed and 15 primer pairs were designed for this species. The survey was conducted by analyzing 21 unrelated individuals. Genetic diversity indexes were calculated. The mean allelic richness was 6.3, the observed heterozygosity was 0.568, and the percentage of polymorphic loci was 93.33%. Also the primers were tested in cross-species amplification and showed promising results for P. droryana, P. emerina, P. lucii, P. meridionalis, P. pugnax, and P. saiqui. The microsatellite loci described here will be useful to evaluate genetic variability of stingless bees, and certainly will improve our knowledge about population dynamics especially in threatened environments.

Very low mitochondrial variability in a stingless bee endemic to cerrado

Partamona mulata is a stingless bee species endemic to cerrado, a severely threatened phytogeographical domain. Clearing for pasture without proper soil treatment in the cerrado facilitates the proliferation of termite ground nests, which are the nesting sites for P. mulata. The genetic consequences of these changes in the cerrado environment for bee populations are still understudied. In this work, we analyzed the genetic diversity of 48 colonies of P. mulata collected throughout the species’ distribution range by sequencing two mitochondrial genes, cytochrome oxidase I and cytochrome B. A very low polymorphism rate was observed when compared to another Partamona species from the Atlantic forest. Exclusive haplotypes were observed in two of the five areas sampled. The sharing of two haplotypes between collection sites separated by a distance greater than the flight range of queens indicates an ancient distribution for these haplotypes. The low haplotype and nucleotide diversity observed here suggests that P. mulata is either a young species or one that has been through population bottlenecks. Locally predominant and exclusive haplotypes (H2 and H4) may have been derived from local remnants through cerrado deforestation and the expansion of a few colonies with abundant nesting sites.

Karyotypic description of four species of Trigona (Jurine, 1807) (Hymenoptera, Apidae, Meliponini) from the State of Mato Grosso, Brazil

The genus Trigona contains at least 31 species, but there have been few cytogenetic studies of this group. In this work, four species of Trigona (T. branneri, T. chanchamayoensis, T. hyalinata, and T. recursa) from the municipality of Cuiaba, in the State of Mato Grosso, Brazil, were studied. In all of the species, the females had 2n = 34 chromosomes and the males had n = 17. The C-banding patterns showed that the karyotypes of these species consisted mainly of acrocentric and pseudoacrocentric chromosomes. These cytogenetic findings should useful in future phylogenetic studies of this group.

A fauna apícola do Parque Municipal da Cachoeirinha (Iporá, GO)

Bees are dependent on flower nectar and pollen (main sources of protein and energy, respectively) and have an important economic and ecological role as pollinators, representing about 40 to 90% of phanerogams pollinators in several ecosystems. This work presents a description of bee species from Parque Municipal da Cachoeirinha in Ipora, Goias state, Brazil. A total of 58 hours of capturing were performed on November and December 2004 and on March and May 2005. A total of 933 individuals were collected, distributed in one family, 16 tribes, 33 genera, and 62 species. Meliponini tribe presented the highest number of individuals and species. Most abundant species were Trigona chanchamayoensis (16.51%), Tetragona clavipes (14.79%) and Apis mellifera and Trigona recursa (12.33%). This work presents the first occurrence in Goias state for six genera and 12 species.