Biology of Bactrocera carambolae (Diptera: Tephritidae) on four hosts

Bactrocera carambolae is a quarantine pest found in Brazil, restricted to the states of Amapá, Pará and Roraima. This fruit fly can potentially cause extensive socioeconomic and environmental damage in the country, if it disperse into areas where fruit is grown for exporting. The objective of this work was to study the biology of B. carambolae on fruits of Averrhoa carambola L. (Oxalidaceae), Psidium guajava L. (Myrtaceae), Spondias mombin L. (Anacardiaceae) and Eugenia stipitata McVaugh (Myrtaceae). The following parameters were investigated: duration of egg-larva, pupal, egg-adult, pre-oviposition, oviposition and post-oviposition periods, pupal weight and viability, sex ratio, fecundity, fertility and longevity. All parameters except pupal weight, oviposition and post-oviposition period, egg fertility and sex ratio were influenced by the host plant on which the larvae were reared. The carambola fruit fly completes its development on all those hosts studied here, with the highest fecundities on A. carambola and P. guajava.     

Phlebotominae and Trichomyiinae (Diptera: Psychodidae) diversity in a tropical dry forest of central Mexico: a comparison of conserved and anthropized habitats

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.     

Schwankungen im Spektrum von Kriebelmückenarten und räumliche Konstanz der Eiablageplätze in einem Niederungsbach (Simuliidae,Diptera). Variation in Species Composition of Black Flies (Simuliidae,Diptera) and Spatial Stability of Oviposition Sites in a Lowland Stream

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.     

On the complementarity of DNA barcoding and morphology to distinguish benign endemic insects from possible pests: the case of Dirioxa pornia and the tribe Acanthonevrini (Diptera: Tephritidae: Phytalmiinae) in Australia

Fruit flies are considered economically important insects due to some species being agricultural pests. However, morphological identification of fruit fly adults and larvae can be difficult requiring a high level of taxonomic expertise, with misidentifications causing problematic false-positive/negative results. While destructive molecular techniques can assist with the identification process, these often cannot be applied where it is mandatory to retain a voucher reference specimen. In this work, we non-destructively (and partial-destructively) processed larvae and adults mostly belonging to the species Dirioxa pornia (Walker, 1849), of the poorly studied nonpest fruit fly tribe Acanthonevrini (Tephritidae) from Australia, to enable molecular identifications whilst retaining morphological vouchers. By retaining the morphological features of specimens, we confirmed useful characters for genus/species-level identification, contributing to improved accuracy for future diagnostics using both molecular and morphological approaches. We provide DNA barcode information for three species of Acanthonevrini known from Australia, which prior to our study was only available for a single species, D. pornia. Our specimen examinations provide new distribution records for three nonpest species: Acanthonevroides variegatus Permkam and Hancock, 1995 in South Australia, Acanthonevroides basalis (Walker, 1853) and D. pornia in Victoria, Australia; as well as new host plant records for D. pornia, from kangaroo apple, apricot and loquat.     

Temperature and Sweet Taste Integration in Drosophila

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Visual and olfactory responses of haematophagous Diptera to host stimuli

Key biotic and environmental constraints on the host-orientated behaviour of haematophagous Diptera are summarized. For each major group of biting Diptera, responses to host stimuli are reviewed, including activation and ranging behaviour, long-range and short-range olfactory responses and visual responses. Limitations to the comparison of results between groups of species, and the practical problems of experimental method and equipment are discussed.     

Vegetation of the Lago de Sanabria area (NW Iberia) since the end of the Pleistocene: a palaeoecological reconstruction on the basis of two new pollen sequences

Various pollen sequences from lacustrine deposits close to Lago de Sanabria (NW Iberia) have for several decades been a key source of information for palaeoenvironmental reconstructions of SW Europe, though their interpretation has been the subject of some controversy. Here we present two new pollen sequences obtained from this area, and a new palaeoenvironmental reconstruction of the region. The available pollen data reach back to before 18,000 b.p., a period of very harsh climate with seasonal (non continuous) sedimentation and a landscape characterised by herbaceous formations dominated by Gramineae and Artemisia, and scrub formations dominated by Ericaceae and Cistaceae. Subsequently sedimentation became continuous, and various regional forest expansions are apparent. At a local level, the first forest expansion began about 12,000 b.p., when Betula pollen reached 70% followed by peaks in Pinus sylvestris-type (>80%) and Quercus robur-type (40%). The Younger Dryas saw a retreat of woodland formations in the area around the lake, with broadleaved deciduous woodland (largely oak) retreating at mid and low altitudes, but with pine woodland persisting in more sheltered sites. The climatic improvement in the Early Holocene favoured re-expansion of woodland, dominated by Pinus sylvestris-type at higher and Quercus robur and Q. pyrenaica at lower altitudes, until anthropogenic deforestation commenced around 4,000 b.p. The disappearance of natural pine woodlands in this region is probably largely attributable to human interference.     

Ultrastructural cytochemistry of the sex pheromone glands of Lutzomyia cruzi male sand flies (Diptera: Psychodidae: Phlebotominae)

The sex pheromone glands of Lutzomyia cruzi male sand flies (Diptera: Psychodidae) were analyzed by cytochemical techniques. In adult males, the epithelium at the fourth abdominal tergite is modified into a glandular epithelium, with large columnar gland cells located side by side. The gland cell cytoplasm contains a large number of mitochondria and peroxisomes, the latter with positive (electron-dense) reaction for catalase, a typical peroxisomal enzyme marker. The gland cell cytoplasm also contains a central vacuolated area, with a large number of electron-lucent vacuoles, not limited by a unit membrane. In well-preserved preparations such vacuoles present a homogenous and slightly electron-dense content, typical of lipid droplets. Indeed, incubation of the tergites with imidazole-buffered osmium tetroxide (to detect lipids) resulted in positive reaction in these vacuoles, as well as in between the microvilli of the gland cells. Use of the osmium–potassium iodide (Os–KI) technique allowed to demonstrate the presence of several endoplasmic reticulum (ER) profiles, as expected in secretory cells. Our data suggest that ER, lipid droplets and peroxisomes are involved in the sand fly pheromone biosynthesis.     

Field parasitism of Ceratitis capitata larvae by Aganaspis daci in Chios, Greece

High parasitism rates were recorded in the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in pupae derived from field infested figs, on the Greek island of Chios in 1999 and 2000. Adult parasitoids were identified as Aganaspis daci (Weld) (Hymenoptera:Eucoilidae), previously known as Trybliographa daci (Weld). Approximately 45%of C. capitata pupae yielded adultparasitoid in both years and the totalmortality of pupae due to the parasitoid was62–65%. Development of male A. daci at25°C, reared on 3rd instar larvaeof C. capitata, was shorter than that of the female (34 and 37 days respectively). Average adultmale longevity was 4–5 days longer than female(16–17 to 11–12 days, respectively) and almostidentical in wild and F₁ parasitoids ofboth sexes. We suggest that A. daci maybe an efficient form of biological control ofC. capitata in the Mediterranean regionand probably in other areas.     

First record of Alysia alticola Ashmead (Hymenoptera: Braconidae) in the Neotropical region

Alysia alticola Ashmead, 1890, is recorded for the first time in central Argentina, reared from pig carcasses. This is also the first mention of the genus Alysia Latreille, 1804, in Argentina, which represents the southernmost record in the Neotropical region.