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Most plant species depend upon insect pollination services, including many cash and subsistence crops. Plants compete to attract those insects using visual cues and floral odor which pollinators associate with a reward. The cacao tree, Theobroma cacao, has a highly specialized floral morphology permitting pollination primarily by Ceratopogonid midges. However, these insects do not depend upon cacao flowers for their life cycle, and can use other sugar sources. To understand how floral cues mediate pollination in cacao we developed a method for rearing Ceratopogonidae through several complete lifecycles to provide material for bioassays. We carried out collection and analysis of cacao floral volatiles, and identified a bouquet made up exclusively of saturated and unsaturated, straight-chain hydrocarbons, which is unusual among floral odors. The most abundant components were tridecane, pentadecane, (Z)-7-pentadecene and (Z)-8-heptadecene with a heptadecadiene and heptadecatriene as minor components. We presented adult midges, Forcipomyia sp. (subgen. Forcipomyia), Culicoides paraensis and Dasyhelea borgmeieri, with natural and synthetic cacao flower odors in choice assays. Midges showed weak attraction to the complete natural floral odor in the assay, with no significant evidence of interspecific differences. This suggests that cacao floral volatiles play a role in pollinator behavior. Midges were not attracted to a synthetic blend of the above four major components of cacao flower odor, indicating that a more complete blend is required for attraction. Our findings indicate that cacao pollination is likely facilitated by the volatile blend released by flowers, and that the system involves a generalized odor response common to different species of Ceratopogonidae.

Se presenta el primer relevamiento de Ceratopogonidae de la Reserva Natural Integral Punta Lara, en la provincia de Buenos Aires. Este área protegida representa uno de los relictos más australes de la selva en galería, donde el conocimiento de la fauna de insectos es aún limitado. Las capturas se realizaron en ambientes de pastizal y selva en galería, con trampas Malaise y trampas de luz, tipo CDC y embudo. Un total de 4.195 especímenes pertenecientes a nueve géneros y 39 especies de Ceratopogonidae fueron identificados. Se brinda un listado de las especies presentes en el área, y se proveen datos de su distribución geográfica. Veintitrés especies se citan en la Reserva por primera vez, mientras que Dasyhelea mediomunda Minaya, Forcipomyia (Forcipomyia) taragui Marino, Spinelli & Cazorla, Forcipomyia (Microhelea) fuliginosa (Meigen), Stilobezzia (Eukraiohelea) elegantula (Johannsen) y Stilobezzia (Stilobezzia) punctulata Lane se registran por primera vez en la provincia de Buenos Aires., We present the results of the first survey on the Ceratopogonidae from the “Reserva Natural Integral Punta Lara”, in Buenos Aires province. This protected area represents the southernmost relict of gallery forest where the knowledge of the insect fauna is still limited. Catches were conducted in areas of grassland and marginal forest with Malaise traps, CDC light traps and funnel light traps. A total of 4,195 specimens belonging to nine genera and 39 species of Ceratopogonidae were identified. A list of the species present in the protected area is provided, along with their distributional data. Twenty-three species are recorded from the reserve for the first time, while Dasyhelea mediomunda Minaya, Forcipomyia (Forcipomyia) taragui Marino, Spinelli & Cazorla, Forcipomyia (Microhelea) fuliginosa (Meigen), Stilobezzia (Eukraiohelea) elegantula (Johannsen) and Stilobezzia (Stilobezzia) punctulata Lane are recorded for the first time in Buenos Aires province., Facultad de Ciencias Naturales y Museo, Centro de Estudios Parasitológicos y de Vectores, Instituto de Limnología "Dr. Raúl A. Ringuelet"

Two new species of Dasyhelea Kieffer, D. yunga and D. allegrae, placed in the grisea and mutabilis speciesgroups respectively, are described, illustrated and photographed based on pupae and male and femaleadults. In addition, the immatures of D. azteca are described for the first time. The specimens werecollected in the southernmost area of the Argentinean Yungas. The pupae of D. yunga and D. allegraewere examined using a Compound Microscope (CM), while the larva and pupa of D. azteca by a ScanningElectron Microscope (SEM) and CM. Fil: Diaz, Maria Florentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Spinelli, Gustavo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentina Fil: Ronderos, Maria Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina

I studied a dataset of surface sediment samples from 80 lakes with zoological macroremain analysis to assess the potential of fossil ceratopogonids (Diptera: Ceratopogonidae), ephemeropterans (Insecta: Ephemeroptera), trichopterans (Insecta: Trichoptera) and oribatid mites (Acarina: Oribatida) as palaeolimnological indicators in Finland. Results showed that late-winter hypolimnetic oxygen and climatic variables were most important in influencing the occurrence and abundance of these taxa. Of the ceratopogonids, the Bezzia type was an indicator of elevated hypolimnetic oxygen conditions, warm climate and oligotrophy, while the Dasyhelea type indicated low hypolimnetic oxygen conditions, moderately cool climate and mild acidity. Ephemeropterans, trichopterans and oribatids indicated warm climatic conditions and oribatids were also indicative of elevated oxygen conditions and small oligotrophic lakes. Results of this study can be useful in palaeolimnological studies because the fauna examined provides a valu...

A new species of the genus Dasyhelea Kieffer, Dasyhelea hanoiensis sp. nov. is described by adult from Hanoi, Vietnam.

Eleven species of Ceratopogonidae are recognized on the Galápagos Islands. Four of these appear to be endemic, six are widespread occurring elsewhere on the continental Americas and one is of uncertain distributional status. One of the endemic species is described as new, Dasyhelea sinclairi Borkent. Each of the species is most closely related to taxa occurring elsewhere than on the Galápagos Islands (with one possible but unlikely exception of two of these being sister species), indicating at least ten independent invasions of the islands by the ancestors or ancestral populations of these species. It is uncertain whether the widespread species have been brought through the agency of man or through natural dispersal to the Galápagos Islands. Based on comparisons with the Ceratopogonidae fauna of oceanic islands elsewhere, the presence of endemic species only in the genera Forcipomyia and Dasyhelea on the Galápagos Islands is likely due to the superior dispersal capabilities of members of these genera. This may also explain the presence of those ceratopogonid species occurring both on the Galápagos Islands and the New World mainland.

Larval habitats and adult emergence sites of the dominant ceratopogonid species were identified from a 14.6-ha site on Sea Island, a coastal Georgia barrier island, during a 14-mo period. Culicoides larvae (5,717) were identified from salt marsh soil samples and were compared on the basis of vegetation, elevation, pH, and soil minerals. Culicotdes furens (Poey) larvae were significant for vegetation and calcium ion content and were most abundant in areas of Spartina alternifiora ( 1.2 m) at elevations near the mean low-tide mark. Numbers of larval C. hollensis were significantly related to vegetation and presence of potassium ions. C. melleus (Coquillett) larvae were significant for soil pH and were found in areas of Distichlis spicata at elevations near the high-tide level. All species occurred in acidic soils (mean pH 5.6). Other ceratopogonids encountered were Dasyhelea atlantis Wirth and Williams, D. mutabilis (Coquillett) and Leptoconops linleyi Wirth and Atchley; L. ltnleyi was found for the first time in Georgia. The relative seasonal abundance of the instars was compared with adult abundance. Lower larval densities of C. hollensis and C. melleus during spring and fall coincided with periods of adult abundance. Higher larval densities during winter and summer correlated with the bimodal spring-fall seasonal abundances of adult C. hollensis and C. melleus .

The ceratopogonid fauna of Guam has attracted minimal interest since the 1959 survey of the insects of Micronesia. We report on new distribution records for three species previously unknown from the island of Guam: Culicoides peliliouensis Tokunaga, Dasyhelea carolinensis Tokunaga, and Dasyhelea dupliforceps Tokunaga.

A longitudinal study to investigate the natural hosts and occurrence of the mosquito pathogenic fungus, Culicinomyces clavisporus was conducted at the Nattai River, Mittagong, New South Wales. The fungus was isolated from Aedes rupestris on 16 occasions, Aedes rubrithorax on 1 occasion, Aedes sp. on 1 occasion, Dasyhelea sp. on 8 occasions, a Chironomidae larva on 1 occasion and moist sediment once. With the exception of 1 isolate, which was from an Aedes larva in a groundpool, all of the infected larvae were collected from small rockpools on a trachyte weir. The study indicated the fungus did not persist and recycle in those rockpools but was washed in when river levels rose. The occurrence of the fungus had a seasonal bias, with 24 of 28 isolates obtained in the cooler months of April to August. Possible reasons for this are discussed.

A new species of Paradasyhelea Macfie is described from females found on the Auckland Islands, New Zealand, and a key is presented to separate it from its five known congeners. New distribution and habitat records are presented for the three ceratopogonid species previously reported from the subantarctic islands of New Zealand—Forcipomyia kuscheli Sublette & Wirth, F. tapleyi Ingram & Macfie, and Dasyhelea aucklandensis Sublette & Wirth.

In field collections of Diptera associated with approximately 12 000 cocoa flowers in Bahia State, Brazil, 66% of the total catch consisted of Cecidomyiidae, 33% of Ceratopogonidae and 2% of Chironomidae and Psychodidae. The ceratopogonid species collected included Forcipomyia (F.) sp., F. (F.) genualis (Lw.), F. (F.) harpegonata Wirth & Soria, F. (F.) pictoni Macfie, three species of Forcipomyia (Euforcipomyia) sp., F. (E.) bromeliae Saund., F. (E,.) quasiingrami Macfie or near species, Forcipomyia (Thyridomyia) jipajapae Wirth, F. (Warmkea) lesliei Wirth, F. (Microhelea) fuliginosa (Mg.), Atrichopogon sp., Dasyhelea sp., Culicoides glabellus Wirth & Blanton and C. paraensis (Goeldi). There was some evidence that F. genualis or near species, Atrichopogon sp., Dasyhelea sp., and some species of Cecidomyiidae may pollinate cocoa. Of nine different organic substrates investigated as potential breeding sites, most species of Ceratopogonidae were reared from epiphytic bromeliads, rotting jackfruit, rotting banana stems and rotting cocoa pod husks.

Dasyhelea esakii Tokunaga, D. intonsa sp. n. for D. perfida sensu Tokunaga and Murachi non Johannsen, Forcipomyia borbonica Clastrier and F. chrysolopha (Kieffer), are recorded from the Cocos (Keeling) Islands.

The role of habitat duration in effecting the distribution of fly larvae in tropical rain pools is examined. Field observations over a complete rainy season show that the duration of each pool varies considerably in response to the pattern of rainfall. Pools of short duration (less than 1 wk) are occupied by Polypedilum vanderplanki or Dasyhelea thompsoni larvae which have physiological adaptations to desiccation. Larvae of a third species, Chironomus imicola which lack drought resistance only occupy the larger pools at the height of the rains when durations are extended to several weeks. As the rains diminish and durations become reduced, drought resistant D. thompsoni replace C. imicola larvae in certain pools. Experiments support field observations that the latter species is restricted to pools of long duration and reveal that the relatively stable water level in such pools adversely affects oviposition by D. thompsoni. The contribution of pool duration and other factors to the maintenance of a single species of fly larva in each pool is discussed.