Intra-puparial development of Lucilia eximia (Diptera, Calliphoridae) / Desenvolvimento Intra-pupal de Lucilia eximia (Diptera: Calliphoridae)

There are few studies about the intra-puparial development in Diptera, nonetheless its importance has been increased because several dipteran species are of forensic interest. Studies on the life cycles of flies often disregard the changes that occur inside the pupae. The objectives of this research were to analyze the intra-puparial development of Lucilia eximia, and to describe chronological and morphological changes that occur during this stage. Around 1.600 specimens were laboratory-reared. The pre-pupae were identified by the reduction of their size and change in coloration, and 10 individuals were sampled every three hours (n=1.000) until adult emergence. The specimens were fixed in 96% alcohol, subsequently immersed in Canoy solution for 24 hours and in formic acid (5%) for 48 hours, to facilitate dissection and analysis of the morphological changes of the individuals. Four stages of the intra-pupal development of L. eximia were observed: 1) Larva-pupa apolysis, which lasted 23 ± 1.08 h; 2) Cryptocephalic pupa, 5 ± 0.53 h; 3) Phanerocephalic pupa, 92 ± 1.94 h; and 4) Pharate adult: Transparents eyes, 125 ± 2.15 h; Yellow eyes, 23 ± 0.89 h; Pink eyes, 14 ± 0.73 h; and Red eyes, 20 ± 0.60 h. The pharate adult is completely formed after 296 hours and the emergence of the adult occurred after 302 ± 3.81 h. In addition, there were included the stage of pre-pupa, pupariation and the beginning of the adult stage, Imago and adult emergence. Each stage is described and compared with those described for Chrysomya albiceps (Calliphoridae).

No mundo existem poucos estudos sobre o desenvolvimento intrapupal de Diptera. Comumente, os estudos dos ciclos de vida das espécies de moscas são feitos eliminando o desenvolvimento embrionário que é muito importante, principalmente nas espécies de interesse forense. O principal objetivo foi o de analisar o desenvolvimento intrapupal de Lucilia eximia, descrevendo as mudanças morfológicas que ocorrem durante o desenvolvimento intrapupal. Foram analisados cerca de 1.600 espécimes cultivados em laboratório. Foram analisadas as fases de pré-pupa, pupa, o início da fase adulta, a imago e a emergência. Pré-pupas foram identificadas de acordo com a redução no tamanho e na alteração da coloração. Dez espécimes foram coletados a cada três horas (n=1.000), sem interrupção, até a emergência dos adultos. As pupas foram fixadas em etanol a 96%. Em seguida foram imersas em solução Carnoy por 24 horas e ácido fórmico a 5% por 48 horas para facilitar a dissecação e análises das alterações morfológicas. Foram determinados 4 estágios de desenvolvimento intrapupal. 1) Apólise larva-pupa com duração de 23 ± 1,08 h; 2) Pupa criptocefálica: 5 ± 0,53 h; 3) Pupa fanerocefálica: 92 ± 1,94 h e; 4) Adulto farado: olhos transparentes: 125 ± 2,15 h; olhos amarelos: 23 ± 0,89 h; olhos róseos: 14 ± 0,73 h e olhos vermelhos 20 ± 0,60 h. O adulto farado estava completo após 296 horas e a emergência dos adultos ocorreu com 302 ± 3,81 h. Cada fase foi descrita e comparada com o descrito para Chrysomya albiceps (Calliphoridae).

A bioassay method for black flies (Diptera: Simuliidae) using larvicides

Esta nota apresenta um método alternativo para bioensaios com larvas de simulídeos, com que se espera proporcionar aos pesquisadores uma ferramenta mais simples, porém igualmente efetiva para a obtenção de dados referentes à eficácia de larvicidas.

Karyotype characterization of Anastrepha fruit flies (Diptera: Tephritidae)

The study comprises the description of the C-banded mitotic chromosomes of five species of Anastrepha, A. amita Zucchi, A. turpiniae Stone, A. zenildae Zucchi, A. grandis (Macquart) and A. leptozona Hendel , and a reanalysis of the chromosomes of three other species, A. distincta Greene, A. obliqua (Macquart) and A. sororcula Zucchi. The species have a diploid number of 12, while A. leptozona has 2n = 10. Heteromorphism of the sex chromosomes is present in all of the species, which have a XY/XX sex chromosome system. A. grandis and A. leptozona have meta and submetacentric autosomes while all of the chromosomes in the other species are acrocentric. The species can be characterized unequivocally by the length and the pattern of blocks of heterochromatin in the sex chromosomes.

O estudo apresenta a descrição dos cromossomos mitóticos, através do bandamento-C, de cinco espécies de Anastrepha, A. amita Zucchi, A. turpiniae Stone, A. zenildae Zucchi, A. grandis (Macquart) and A. leptozona Hendel e uma reanálise dos carótipos de três outras espécies, A. distincta Greene, A. obliqua (Macquart) and A. sororcula Zucchi, segundo a mesma técnica. As espécies apresentam número diplóide igual a 12 cromossomos, exceto A. leptozona com 2n = 10. Os cromossomos sexuais são heteromórficos e com sistema XX/XY. Os autossomos são meta ou submetacêntricos em A. grandis and A. leptozona e acrocêntricos nas demais espécies. Os cromossomos sexuais apresentam comprimento e padrão de blocos de heterocromatina característicos para cada espécie.

Expression of dorsal-ventral genes during early development of Rhynchosciara americana embryos

The establishment of dorsal-ventral polarity in Drosophila is a complex process which involves the action of maternal and zygotically expressed genes. Interspecific differences in the expression pattern of some of these genes have been described in other species. Here we present the expression of dorsal-ventral genes during early embryogenesis in the lower dipteran Rhynchosciara americana. The expression of four genes, the ventralizing genes snail (sna) and twist (twi) and the dorsalizing genes decapentaplegic (dpp) and zerknüllt (zen), was investigated by whole-mount in situ hybridization. Sense and antisense mRNA were transcribed in vitro using UTP-digoxigenin and hybridized at 55°C with dechorionated fixed embryos. Staining was obtained with anti-digoxigenin alkaline phosphatase-conjugated antibody revealed with NBT-BCIP solution. The results showed that, in general, the spatial-temporal expression of R. americana dorsal-ventral genes is similar to that observed in Drosophila, where twi and sna are restricted to the ventral region, while dpp and zen are expressed in the dorsal side. The differences encountered were subtle and probably represent a particular aspect of dorsal-ventral axis determination in R. americana. In this lower dipteran sna is expressed slightly later than twi and dpp expression is expanded over the lateral ectoderm during cellular blastoderm stage. These data suggest that the establishment of dorsal-ventral polarity in R. americana embryos follows a program similar to that observed in Drosophila melanogaster.

Estudo da dispersão larval radial pós-alimentar em Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae) / Study of postfeeding larval radial dispersal in Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae)

Blowflies utilize discrete and ephemeral sites for breeding and larval nutrition. After the exhaustion of food, the larvae begin dispersing to search for sites to pupate or to additional food source, process referred as postfeeding larval dispersal. Some of the most important aspects of this process were investigated in Chrysomya megacephala, utilizing a circular arena to permit the radial dispersion of larvae from the center. To determinate the localization of each pupa, the arena was split in 72 equal sectors from the center. For each pupa, distance from the center of arena, weight and depth were determined. Statistical tests were performed to verify the relation among weight, depth and distance of burying for pupation. It was verified that the larvae that disperse farther are those with higher weights. The majority of individuals reached the depth of burying for pupation between 7 and 18 cm. The study of this process of dispersion can be utilized in the estimation of postmortem interval (PMI) for human corpses in medico-criminal investigations

Desenvolvimento pós-embrionário de lucilia cuprina diptera calliphoridae criada em dieta a base de carne equina em diferentes estágios de putrefacao / Postembrionary development of lucilia cuprina reared on horse meat exposed at different periods of putrefaction

O objetivo deste estudo foi comparar a influência de diferentes fases verificar o desenvolvimento embrionário de Lucilia cuprina em dieta a base de carne eqüina (duas, 24, 48, 72 e 96 horas) sobre o desenvolvimento embrionário. Utilizaram-se 60 gramas de dieta por repetição/tratamento, considerando-se a relaÇão de 1 larva/2g de substrato. Foram utilizadas quatro repetiÇões por tratamento. Os resultados obtidos indicaram que a duraÇão da fase e pupal oriunda deste substrato foi, em média, menor nos tratamentos relativo a 2 e 24 horas, respectivamente, refletindo-se, em uma reduÇão da massa corporal, ocorrendo o inverso nos tratamento de 72 e 96 horas. A taxa de emergência dos adultos foi superior a 50 por ciento em todos os tratamentos

The immature stage of Protodasyapha (Protodasyapha) hirtuosa (Philippi) and their campararison with the immature stages of other Pangoniini (Diptera: Tabanidae: Pangoniinae)

The terrestrial immature stages of the Chilean horse fly, Protodasyapha (Protodasyapha) hirtuosa (Philippi), are described. P. (P.) hirtuosa resembles Ectenopsis vulpecula Macquart and Caenoprosopon trichocera (Bigot) from Australia, and Esenbeckia delta Hine from North America, in both the larval and pupal stages. Some characters that are shared between these species are unique and provide evidence of their monophyletic origin. Larvae of P. hirtuosa were found 3-5 below of the soil surface and associated with larvae of Coleoptera, Lepidoptera and Diptera.

The preimaginal stages of Cryptotylus unicolor (Wiedemann) and Tabanus nebulosus ornativentris Kroeber (Tabanidae-Diptera-Insecta)

A larva with peculiar very long pubescence on the integument, the pupa of Cryptotylus unicolor, and the larva and pupa of Tabanus nebolosus ornativentris are described and illustrated.

External morphology of the immature stages of Metacuterebra apicalis

The second and the third instar larvae, and the pupa of Metacuterebra apicalis (Guerin-Menevilli), are described based on light and scranning electron microscope observations.

Diffusion model applied to postfeeding larval dispersal blowflies (Diptera: Calliphoridae)

This paper presents a diffusion model of larval dispersal especifically designed to account for particular aspects of postfeeding larval dispersal from the food source in organisms such as blowflies. In these organisms the dispersal of immatures includes two groups of individuals, those that are actively migrating and those that initiated the pupation process. The classical diffusion equation in one dimension was modified to incorporate a function which describes the burying of larvae to become pupae. The analytical solution of this equation predicts oscillatory and monotonic dispersal behaviors, which are observed in experimental populations of blowfly species.