RESUMO
Carrion beetles are part of the great diversity of insects collected on cadavers. In Brazil, beetles of the genus Oxelytrum have great forensic importance in post mortem interval (PMI) estimation. We investigated the system of chemical communication in the attraction of these necrophagous beetles. Gas chromatographic analysis (GC) of female and male aeration extracts revealed the presence of two male-specific compounds, produced in a ratio of 94:6. Bioassays showed that the combination of male produced volatiles and the odor of a food source (carcass volatiles) were attractive to females. Mass and infrared spectral analyses of the male-specific compounds suggested that they were both unsaturated hydrocarbons. Several micro-derivatizations were carried out with the natural products, and the target structures were identified as (Z)-1,8-heptadecadiene (major) and 1-heptadecene (minor). The structure of the minor component was assigned by co-injection with a commercial standard. A seven-step synthesis was developed to synthesize (Z)-1,8-heptadiene, which co-eluted with the major natural product on three different GC stationary phases. Y-tube olfactometer assays showed that the mixture of synthetic standards in the naturally occurring proportion was slightly attractive to females. The results contribute both to the understanding of the chemical ecology of O. discicolle and to its potential to improve the accuracy of PMI estimation.
Assuntos
Besouros/fisiologia , Atrativos Sexuais/química , Animais , Comportamento Animal/efeitos dos fármacos , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Feminino , Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Odorantes , Atrativos Sexuais/isolamento & purificação , Compostos Orgânicos Voláteis/síntese química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologiaRESUMO
The biodiversity of northern South American and Central American Liogenys Guérin-Méneville, 1831 (Coleoptera: Scarabaeidae: Melolonthinae: Diplotaxini) is reviewed. Four new species are described: L. clipeosetosa Cherman, new species; L. genieri Smith Cherman, new species; L. granadina Cherman, new species; and L. schneiderae Cherman, new species. The male of L. quadridens (Fabricius, 1798) and the female of L. quadridentata Blanchard, 1851 are described for the first time. Liogenys gebieni Moser, 1921 is a new junior subjective synonym of L. macropelma Bates, 1887. The northernmost record of Liogenys is emended to Trinidad and Tobago for L. granadina Cherman, new species and L. schneiderae new species. Diplotaxis puberea cuprascens (Bates, 1887) new combination, Diplotaxis puberea puberea (Bates, 1887) new combination, and Diplotaxis pubisternis (Bates, 1887) new combination are all transferred from Liogenys to Diplotaxis Kirby, 1837. Lectotypes are designated for Liogenys gebieni Moser, 1921; Melolontha quadridens Fabricius, 1798; and Liogenys quadridentatus Blanchard, 1851. An identification key to northern South American Liogenys is presented.
Assuntos
Besouros/classificação , Animais , América Central , Feminino , Masculino , América do SulRESUMO
The biodiversity of Liogenys Guérin-Méneville, 1831 (Coleoptera: Scarabaeidae: Melolonthinae: Diplotaxini) from the southern South American Transition Zone and boundaries is presented. Four new species are described: L. brachyclypeata Cherman, new species; L. lucialmeidae Cherman, new species; L. martinezi Cherman, new species; and L. maxillaricuspis Cherman, new species. The synonymy of L. flaveola Moser, 1924 (= L. kadleci Frey, 1970) is proposed. Lectotypes are designated for L. flavida Moser, 1918; L. pallidicornis Blanchard, 1851 (currently L. xanthocera Harold, 1869); and L. rufoflava Moser, 1918. Redescriptions are provided for all the species mentioned above plus L. calcarata Frey, 1970 and L. kunzteni Moser, 1921, as well as an identification key and updated geographical distributions to all species in the region. All species are present in the Monte province, except of L. kuntzeni (Andean provinces of Chile). Liogenys flavida and L. rufoflava have the broadest distribution, the latter here expanded to Paraguay and Chile.
Assuntos
Besouros , AnimaisRESUMO
Abstract The study of ca. 280 specimens of Cercyon Leach, 1817 (Hydrophilidae: Sphaeridiinae: Megasternini) deposited in the Coleção Entomológica Pe. J.S. Moure, Universidade Federal do Paraná, Brazil, revealed a new species from Atlantic Rain Forest biome in Paraná State (Southern Brazil) and new records. Cercyon (Cercyon) curi sp. nov. is herein described and illustrated, belonging to the Neotropical C. variegatus species group. Cercyon (Cercyon) nigriceps (Marsham, 1802) is recorded for the first time in Paraná State, and Cercyon (Cercyon) inquinatus Wollaston, 1854 from Amazonas State (Northern Region); these records extend the distributional range of both species in Brazil. Cercyon (Cercyon) praetextatus (Say, 1825) is recorded for the first time from Brazil based on specimens collected in Paraná. Those three species were previously recorded as introduced in South America.
RESUMO
Southern Brazil is unique due to its subtropical climate. Here, we report on the first forensic entomology case and the first record of Sarconesia chlorogaster (Wiedemann) in a human corpse in this region. Flies' samples were collected from a body indoors at 20°C. Four species were found, but only Chrysomya albiceps (Wiedemann) and S. chlorogaster were used to estimate the minimum postmortem interval (mPMI). The mPMI was calculated using accumulated degree hour (ADH) and developmental time. The S. chlorogaster puparium collected was light in color, so we used an experiment to establish a more accurate estimate for time since initiation of pupation where we found full tanning after 3 h. Development of C. albiceps at 20°C to the end of the third instar is 7.4 days. The mPMI based on S. chlorogaster (developmental time until the third instar with no more than 3 h of pupae development) was 7.6 days.