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21.
A study of the phlebotomine sand fly fauna was carried out in the Rio Preto State Park (Minas Gerais, Brazil) aiming to associate the presence of vector species with the risk of leishmaniasis transmission in that region. Sand flies were captured using HP light traps for four months from January to October 2013. The traps were exposed continuously for 40 h each month, in nine fixed sites. A total of 3129 sand flies were captured, belonging to 19 species. Lutzomyia evandroi (Costa Lima & Antunes 1936) was the predominant species (76.48%). The distribution of the phlebotomine sand flies and climatic factors (temperature, humidity, and rainfall) was evaluated. The summer was the season with higher occurrence of insects captured (82.4%). The presence of cutaneous and visceral vector species in park areas requires attention and regular monitoring of sand fly fauna in this conservation area to ensure the well-being of visitors and the regional ecotourism.  相似文献   
22.
The species composition of black flies (Simuliidae, Diptera) in a lowland stream of Aller-Leineregion (northern Germany, FRG) is analysed in the course of several years. Normally, Odagmia ornata (MG .) is the dominating species. For a short sharply defined period Boophthora erythrocephala DE GEER appeared in a great number. Possible reasons and related research on spatial stability of oviposition sites are presented.  相似文献   
23.
A revision of the species and families of sarcosaprophagous flies (Diptera: Calliphoridae, Sarcophagidae, Muscidae, Fanniidae, Drosophilidae, Phoridae, Piophilidae and Stratiomyidae) suitable for forensic purposes in the Iberian Peninsula is presented. Morphological characteristics that allow the accurate identification of third instars of the species present in the Iberian Peninsula are described and presented in the form of a diagnostic key. For larval Calliphoridae, characteristics such as the spines of the body segments were useful for the genus Calliphora whereas features of the anal segment and the cephalopharyngeal skeleton were useful for larvae of Lucilia. Identification of three Chrysominae species present in the Iberian Peninsula is included. For larval Sarcophagidae, characters such as the arrangement and shape of spiracular openings, structures of the anal segment and the cephalopharyngeal skeleton were used for the first time. A new record of Sarcophaga cultellata Pandellé, from a human corpse, is also included as well as recent incursions into the European cadaveric entomofauna such as Synthesiomyia nudiseta (van der Wulp) and Hermetia illucens (Linnaeus). This work provides useful new information that could be applied to forensic investigations in the Iberian Peninsula and in southern Europe.  相似文献   
24.
Experimental studies were conducted under both laboratory and field conditions to determine the effects of prey density, three levels of prey aggregation, water depth, and predator density on the number of snails killed per larva of Sepedon fuscipennis. Of these factors, predation rates were most influenced by prey density and water depth. The number of small (2–4.5 mm) Lymnaea palustris killed per larva of S. fuscipennis increased at a decreasing rate as prey density increased under shallow water conditions. Larvae killed a mean of 14 snails at a prey density of 200/m2, while an average of 24 snails were killed per larva of S. fuscipennis at a prey density of 4000/m2. This functional response to prey density was largely confined to third-instar larvae, and as water depth was increased the response was not apparent.A field study in which larval densities of S. fuscipennis were manipulated showed that the population density of smaller individuals of L. palustris (< 4.5 mm) was reduced when predator density was increased. Populations of Physa integra, Gyraulus parvus, and larger L. palustris were not significantly reduced by the malacophagous larvae at the levels tested.  相似文献   
25.
A geometric morphometric analysis was conducted on wing‐vein landmarks on exemplar species of the family Simuliidae of the following genera: Parasimulium, Gymnopais, Twinnia, Helodon, Prosimulium, Greniera, Stegopterna, Tlalocomyia, Cnephia, Ectemnia, Metacnephia, Austrosimulium, and Simulium. Generalized least squares superimposition was performed on landmarks, followed by a principal component analysis on resulting Procrustes distances. Patterns of shape change along the principal component axes were visualized using the thin‐plate spline. The analysis revealed wing shape diversity through (1) the insertion points of the subcosta and R1, resulting in the terminus of the costa exhibiting a trend towards a more apical position on the wing, and (2) the insertion point of the humeral cross vein, resulting in the anterior branch of the media exhibiting a trend toward a more basal position on the wing. Canonical variates analysis of Procrustes distances successfully assigned all exemplar species into their a priori taxonomic groupings. The diversity in wing shape reveals a trend towards decreased length of basal radial cell and increased costalization of anterior wing veins in the evolutionary transition from plesiomorphic prosimuliines to more derived simuliines. The functional significance of these evolutionary transitions is discussed. © 2013 The Linnean Society of London  相似文献   
26.
Tropical tephritids are ideally suited for studies on population divergence and speciation because they include species groups undergoing rapid radiation, in which morphologically cryptic species and sister species are abundant. The fraterculus species group in the Neotropical genus Anastrepha is a case in point, as it is composed of a complex of up to seven A. fraterculus morphotypes proposed to be cryptic species. Here, we document pre‐ and post‐zygotic barriers to gene flow among adults of the Mexican A. fraterculus morphotype and three populations (Argentina, Brazil, and Peru) belonging to two separate morphotypes (Brazilian 1 and Peruvian). We unveiled three forms of pre‐zygotic reproductive isolation resulting in strong assortative mating. In field cages, free‐ranging male and female A. fraterculus displayed a strong tendency to form couples with members of the opposite sex belonging to their own morphotype, suggesting that male pheromone emission, courtship displays, or both intervene in shaping female choice before actual contact and coupling. In addition, males and females of the Peruvian morphotype became receptive and mated significantly later than adults of the Mexican and Brazilian 1 morphotypes. After contact, Mexican females exhibited greater mating discrimination than males when facing adults of the opposite sex belonging to either the Peruvian or the Brazilian 1 morphotype as evidenced by vigorous resistance to penetration once they had been forcefully mounted by heterotypic males. Forced copulations resulted in production of F1 hybrids that were either less viable (and partially fertile) than parental crosses or even sterile. Our results suggest that the Mexican morphotype is a distinct biological entity and that pre‐zygotic reproductive isolation through divergence in courtship or male‐produced pheromone and other mechanisms appear to evolve faster than post‐zygotic isolation in the fraterculus species group.  相似文献   
27.
We recorded and analyzed the diversity of Phlebotominae and Trichomyiinae in two types of landscape (conserved and anthropized) over the course of three seasons (rainy, cold and dry) in southwestern Puebla, Mexico. A total of 578 specimens belonging to five genera and 10 species were obtained. Phlebotominae was represented by eight species, six of them new records for the state of Puebla, and for Trichomyiinae two species were recorded in the state of Puebla for the first time. There were eight species in the anthropized area and 10 species were recorded in the conservation area. The abundance of both subfamilies was high in the conservation area, representing 83.6% of the total sample, whereas in the anthropized area only 16.4% of the total sample was recorded. Eight species were found during the rainy and dry seasons, and seven species during the cold season. Abundance was highest in the dry season (76.30%), and lowest in the rainy season (5.9%). This kind of information is useful for understanding the transmission patterns of visceral leishmaniasis – endemic to central Mexico – by phlebotomine sand flies.  相似文献   
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Abstract.  Flies belonging to the subfamily Steganinae (Drosophilidae) display unusual zoophilic feeding habits at the adult and/or larval stage. Phortica variegata (Fallén) feeds on tears or eye liquid around the eyes of humans and carnivores. When feeding it is a potential vector of Thelazia callipaeda (Railliet and Henry) eyeworms. Adult and larval stages of this fly may be easily confused with other species belonging to the same genus, and little is known on the biology and ecology of P. variegata . In April–November 2005, a total of 969 P. variegata were collected in an area with a high prevalence of canine thelaziosis. The number of flies collected weekly was then related to climatic and environmental parameters (e.g. temperature, relative humidity and total rainfall) recorded daily at the collection site. The highest number of Phortica were collected during July–August. The sex ratio (number of males : females) rose from ∼ 0.5 during May–July, to ∼ 3.0 in August and 181 during September–October. Distributional data, representing 242 sites at which P. variegata has been collected in Europe, were analysed using a desktop implementation of the genetic algorithm for rule-set prediction (GARP) to model ecological requirements across Europe, as well as in Italy. P. variegata is shown to be mainly active at 20–25 °C and 50–75% RH. The ecological niche model suggests with a high degree of confidence that large areas of Europe are likely to represent suitable habitat for this species, mostly concentrated in central Europe. The results reported here contribute basic knowledge on the ecology and geographical distribution of P. variegata flies, which will be fundamental to gaining a better understanding of their role as vectors of human and animal pathogens.  相似文献   
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