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1.
Rev. bras. entomol ; 63(1): 1-5, Jan.-Mar. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045543

RESUMO

ABSTRACT Bait traps are effective and commonly used method in the studies of orchid bees. Important questions in the context of this method, including those related to bait dispersion, how long baits remain attractive, the distance from which males are supposed to be attracted to lures and so on, are still open subjects. Data on the attractiveness of bait traps that have remained in the field during two weeks in a large Atlantic forest preserve are presented. Four main results emerge from the data: (i) the abundance of specimens collected per day decreased in all the attractants as the traps were left on the field; (ii) despite this decrease, the absolute number of individuals collected after eight and fifteen days is remarkably, mostly in eugenol and vanillin baits; (iii) the vast majority of species, 22 of 25, was already collected on the first sample day; (iv) a consistent variation in the relative abundance of individuals collected in each scent as collections were made. We urge that bait traps should not be left in the field beyond what is strictly necessary since there is a real possibility of collecting a significant number of individuals as these traps remain available.

2.
Theory Biosci ; 135(3): 111-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27067711

RESUMO

Insects in the order Hymenoptera (bees, wasps and ants) present an haplodiploid system of sexual determination in which fertilized eggs become females and unfertilized eggs males. Under single locus complementary sex-determination (sl-CSD) system, the sex of a specimen depends on the alleles at a single locus: when diploid, an individual will be a female if heterozygous and male if homozygous. Significant diploid male (DM) production may drive a population to an extinction scenario called "diploid male vortex". We aimed at studying the dynamics of populations of a sl-CSD organism under several combinations of two parameters: male flight abilities and number of sexual alleles. In these simulations, we evaluated the frequency of DM and a genetic diversity measure over 10,000 generations. The number of sexual alleles varied from 10 to 100 and, at each generation, a male offspring might fly to another random site within a varying radius R. Two main results emerge from our simulations: (i) the number of DM depends more on male flight radius than on the number of alleles; (ii) in large geographic regions, the effect of males flight radius on the allelic diversity turns out much less pronounced than in small regions. In other words, small regions where inbreeding normally appears recover genetic diversity due to large flight radii. These results may be particularly relevant when considering the population dynamics of species with increasingly limited dispersal ability (e.g., forest-dependent species of euglossine bees in fragmented landscapes).


Assuntos
Alelos , Distribuição Animal , Diploide , Himenópteros/fisiologia , Comportamento Sexual Animal , Animais , Simulação por Computador , Feminino , Variação Genética , Haploidia , Heterozigoto , Masculino , Modelos Estatísticos , Dinâmica Populacional , Processos de Determinação Sexual
3.
Rev. bras. entomol ; 58(4): 356-370, Oct.-Dec. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-732848

RESUMO

Conservation of mayflies (Insecta, Ephemeroptera) in Espírito Santo, southeastern Brazil. Ephemeroptera exhibits great diversity among bodies of freshwater in the Atlantic Forest, a biome that is suffering from massive human impact. Within this context, the creation of conservation units using biological information is more recommended than economic, cultural, or political criteria. The distribution pattern of 76 Ephemeroptera species was analyzed using the biogeographical methods Parsimony Analysis of Endemicity and Network Analysis Method in order to infer relevant areas for conservation of the mayfly community in Espírito Santo. The results obtained from both analyses were largely congruent, and pointed out four relevant areas for conservation: two in the south of the state, where conservation units or priority areas for conservation are well established; and two in the north, a region in the state where little conservation efforts have been historically done. Therefore, based on our analyses on mayflies, we recommend the expansion of the existing APCs or the creation of new APCs on the north of Espírito Santo.

4.
Rev. bras. entomol ; 49(2)jun. 2005. ilus
Artigo em Português | LILACS | ID: lil-415168

RESUMO

Palpibracus Rondani é um gênero de Muscidae que aloca 16 espécies, incluindo Palpibracus darwini sp. nov., descrita com base em espécimens macho de Concepción, Chile. Foi realizada uma análise cladística baseada em 31 caracteres morfológicos de adultos e utilizando 12 espécies como grupos externos. A análise mostrou que Palpibracus é um gênero monofilético cujo grupo-irmão é o gênero Brachygasterina. O relacionamento entre as espécies foi: (P. veneris ((P. albuquerquei (P. peruvianus, P. trivittatus)) (P. fasciculatus, P. nigriventris)) ((P. spicatus, P. uvivittatus) (P. lancifer (P. darwini sp. nov. (P. chilensis, P. confusus (P. pilosus ( P. similis (P. separatus, P. carvalhoi)))))))). Palpibracus apicalis Malloch foi alocada tentativamente em Psilochaeta Stein. É apresentada também uma chave para as espécies de Palpibracus.


Assuntos
Animais , Masculino , Feminino , Dípteros/classificação , Filogenia
5.
Rev. bras. entomol ; 48(3): 431-431, jul.-set. 2004.
Artigo em Inglês | LILACS | ID: lil-384850

RESUMO

Nova combinação em Brachygasterina Macquart (Diptera, Muscidae). É proposta uma nova combinação, Brachygasterina valdiviensis (Pamplona & Couri, 2000) comb. nov., anteriormente alocada em Palpibracus Rondani, 1863. São indicadas suas afinidades com B. violaceiventris Macquart, 1851, espécie estreitamente relacionada.


Assuntos
Animais , Muscidae/anatomia & histologia , Muscidae/classificação
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