Chorion patterns on eggs of Lutzomyia sandflies from the Peruvian Andes

Abstract. Scanning electron microscopy (SEM) was used to depict and describe the eggs of five species of phlebotomine sandfly from the Andean region of Peru: Lutzomyia caballeroi, Lu.noguchii, Lu.peruensis, Lu.tejadai and Lu.verrucarum. Two new types of chorionic sculpturing of sandfly eggs are reported: these were named disperse (Lu.tejadai) and verrucose (Lu.noguchii). The aeropylar area of the eggs is also described for the first time for neotropical sandflies. These character states appear to vary for ecological rather than phylogenetic reasons and could be used for species identification.     

Anopheles culicifacies in Baluchistan, Iran

Abstract. Anopheles culicifacies (probably species A) is the main vector of malaria in Baluchistan, southeastern Iran. Adult mosquitoes were collected during 1990-92 by five methods of sampling: knock-down pyrethrum space-spray indoors, human and animal bait (18.00–05.00 hours), pit shelters and CDC light traps, yielding 62%, 3%, 6%, 4% and 25% of specimens, respectively. Whereas spray-catches comprised c. 70% gravid and semi-gravid females, light trap catches were mostly ( c . 60%) unfed females, while females from pit shelters comprised all abdominal stages more equally (13–36%). An. culicifacies populations peaked in April-May and rose again during August-November. Densities of indoor-resting mosquitoes were consistently greater in an unsprayed village than in villages subjected to residual house-spraying with propoxur, malathion or pirimiphos-methyl. Monthly malaria incidence generally followed fluctuations of An. culicifacies density, usually with a peak in May-June.     

The efficacy of indoor CDC light traps for collecting the sandfly Phlebotomus argentipes, vector of Leishmania donovani

The efficacy of light traps for collecting sandflies (Diptera: Psychodidae) varies both inter-specifically and intra-specifically (by gender and physiological status) as a result of significant differences in phototropic and other behavioural characteristics. The efficacy of miniature CDC light traps for collecting Phlebotomus argentipes Annandale & Brunetti, a vector of Leishmania donovani Laveran & Mesnil (Kinetoplastida: Trypanosomatidae), was assessed in the Indian state of Bihar. Sandflies were collected during the night from 16 houses in each of three villages over 3 months (four times at fortnightly intervals) using CDC light traps indoors, and by aspirator collection (carried out by one person for 30 min/house) from the walls of the same houses the following morning. Incidence rate ratios (IRRs) between CDC light trap collections and aspirator collections were obtained through a negative binomial regression with household as random effect. CDC light traps were especially effective in catching males (IRR 3.08, 95% confidence interval [CI] 2.12-4.46) and unfed females (IRR 3.50, 95% CI 2.37-5.16) of P. argentipes, and to a lesser extent gravids (IRR 1.77, 95% CI 1.07-2.93). However, only a relatively small proportion of all blood-fed P. argentipes were collected by light trap (IRR 0.45, 95% CI 0.28-0.73). Despite its limitations in collecting blood-fed female sandflies, the CDC light trap appears to trap a sufficient proportion of the indoor population of sandflies for sampling purposes, and as this light trap is also more convenient and more easily standardized than the aspirator method, we conclude that it is the most efficient method for monitoring P. argentipes populations in the Indian subcontinent.     

Phlebotomine sandfly responses to carbon dioxide and human odour in the field

Responses of Lutzomyia sandflies (Diptera: Psychodidae: Phlebotominae) to carbon dioxide (CO2) and human odour were investigated by field experiments in Parana State, southern Brazil. Catches of two predominant species: Lu. intermedia (Antunes & Coutinho) and Lu. whitmani Lutz & Neiva, were compared between traps baited with a human adult or with CO2 emitted at the human-equivalent rate. When the baits were only 40 cm apart, no difference of attractiveness was detected. When baits were separated by 20 m, however, significantly fewer sandflies (44% Lu. intermedia, 46% Lu. whitmani) were trapped with CO2 compared with human bait. This is the first field evidence that anthropophilic sandflies are attracted by human kairomones in addition to CO2. For both species [Lutzomyia intermedia and Lu. whitmani] [corrected], the proportion of human attractiveness attributable to CO2 was significantly more [corrected] for males than females; for Lu. intermedia males human bait was no more attractive than CO2 alone. Gender differences in sandfly olfactory sensitivity are likely to be associated with behavioural differences on the host, where females feed on blood and males find mates. With traps 20 m apart, both Lutzomyia spp. showed roughly linear increased responses (log-log scale) to 0.08-0.55% CO2 equivalent to 0.5-4 humans. This would explain why host size is generally proportional to attractiveness, as observed for other species of phlebotomine sandflies.     

An association between phlebotomine sandflies and aphids in the Peruvian Andes

Abstract. As the composition of natural sugars in the diet of adult sandflies (Diptera: Psychodidae: Phlebotominae) may affect the development of Leishmania (Kinetoplastida: Trypanosomatidae) in sandfly guts, and so play an important role in the epidemiology of leishmaniasis, there is increasing interest in the sources of sugars for wild sandflies. Advanced chromatography techniques have provided indirect evidence that wild sandflies feed on honeydew, a substance released by aphids (Hemiptera: Aphididae) when feeding. Our objective was to determine whether sandfly density can be influenced directly by the local density of aphids. Aphid density was determined by counting absolute numbers of aphids on alfalfa stems in Purisima Valley, Peru, where sandflies transmit Leishmania peruviana causing Andean cutaneous leishmaniasis (uta). Sandfly relative abundance was measured using sticky trap sampling repeatedly in alfalfa fields. Lutzomyia verrucarum accounted for 92% of the total sandflies collected. As there was a female bias in sandflies collected close to houses, only the numbers of male sandflies were used in analysis. Most of the adult aphids found feeding on alfalfa were either Therioaphis trifolii forma maculata (97%) or Acyrthosiphon pisum (3%). By regression analysis, a significant relationship was found between the density of Lu. verrucarum males and the density of adults of both aphid species. This is the first ecological study to support the hypothesis that aphid honeydew may be a source of sugar for sandflies.     

Evaluation of deltamethrin-impregnated bednets and curtains against phlebotomine sandflies in Valle del Cauca, Colombia

Abstract. The effectiveness of bednets and curtains (nylon mesh 64 per cm²) impregnated with deltamethrin at 26 mg a.i./m² in reducing the biting nuisance caused by three phlebotomine sandfly species: Lutzomyia columbiana, Lu. lichyi and the predominant Lu. youngi (Diptera: Psychodidae), was evaluated at La Guaira, a rural settlement in Valle de Cauca near Cali, Colombia.
Pairs of volunteers collected sandflies under impregnated bednets, in rooms protected by impregnated curtains or in unprotected rooms in a randomized matched design. Collections were made in three houses per night on three consecutive nights, so that each house was sampled under each of the three treatments. This routine was repeated at 2-week intervals for 6 months. There was no significant difference between the overall numbers of sandflies collected in rooms with or without impregnated curtains. Only 0.14 sandflies/man-hour were caught on human bait under impregnated bednets, significantly fewer than the numbers collected on human bait outside the nets in the same room (1.91) or in unprotected rooms (3.29).
In a second set of experiments carried out in La Guaira and the neighbouring community of Jiguales, the effect of deltamethrin impregnation was evaluated by comparing numbers of sandflies collected on human bait under treated and untreated nets. Significantly fewer were collected under the impregnated nets (0.25 v. 0.69/man-hour). Wild-caught female Lu. youngi exposed to treated netting for 2 min in the laboratory all died with 24 h. The impact of deltamethrin-impregnated bednets was considered to be useful against Lu. youngi and other potential vectors of leishmaniasis in such communities.     

Anopheles arabiensis and An. gambiae chromosomal inversion polymorphism, feeding and resting behaviour in relation to insecticide house-spraying in Tanzania

Abstract. Differential responses of the mosquitoes Anopheles arabiensis and An. gambiae sensu stricto to house-spraying with DDT or lambda-cyhalothrin were evaluated in relation to chromosomal inversion polymorphism, feeding and resting behaviour of these malaria vectors in Tanzania. Blood-fed mosquitoes from pit traps outdoors, exit traps on windows and indoor-resting catches were identified cytogenetically and the chromosomal inversion frequencies compared between samples and species. Their outdoor-resting behaviour was assessed by a mark–release–recapture experiment and by determining the proportion of freshly blood-fed individuals in exit traps. The source of bloodmeals was analysed by an ELISA method. Endophagic females of An. arabiensis were more likely than those of An. gambiae to exit from a house on the night of blood-feeding. Only in one out of three villages was there evidence that chromosomally distinct individuals within a species had different preferences for resting sites. There were indications, but not conclusive evidence, that mosquitoes caught indoors or outdoors had a tendency to return to the same type of resting site. In villages sprayed with either insecticide, the mean age of the vector populations was greatly reduced, compared with those in the unsprayed villages. An. arabiensis females exited from DDT sprayed houses after blood-feeding, whereas with lambda-cyhalothrin those exiting were mostly unfed and there was a decline in the human blood index. The excitorepellency of DDT was perceived as a disadvantage, whereas lambda-cyhalothrin apparently had more impact on malaria transmission by An. arabiensis.     

Performance of light‐emitting diode traps for collecting sand flies in entomological surveys in Argentina

The performance of two light‐emitting diode traps with white and black light for capturing phlebotomine sand flies, developed by the Argentinean Leishmaniasis Research Network (REDILA‐WL and REDILA‐BL traps), were compared with the traditional CDC incandescent light trap. Entomological data were obtained from six sand fly surveys conducted in Argentina in different environments. Data analyses were conducted for the presence and the abundance of Lutzomyia longipalpis, Migonemyia migonei, and Nyssomyia whitmani (106 sites). No differences were found in presence/absence among the three types of traps for all sand fly species (p>0.05). The collection mean of Lu. longipalpis from the REDILA‐BL didn´t differ from the CDC trap means, nor were differences seen between the REDILA‐WL and the CDC trap collection means (p>0.05), but collections were larger from the REDILA‐BL trap compared to the REDILA‐WL trap (p<0.05). For Mg. migonei and Ny. whitmani, no differences were found among the three types of traps in the number of individuals captured (p>0.05). These results suggest that both REDILA traps could be used as an alternative capture tool to the original CDC trap for surveillance of these species, and that the REDILA‐BL will also allow a comparable estimation of the abundance of these flies to the CDC light trap captures. In addition, the REDILA‐BL has better performance than the REDILA‐WL, at least for Lu. longipalpis.     

Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis

Abstract. To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis , the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m^-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m² cotton sheets as 'targets' (focal coverage).
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans.     

Phlebotomine sandflies and leishmaniasis risks in Colombian coffee plantations under two systems of cultivation

The phlebotomine sandfly fauna of traditional (shaded) and intensified (unshaded) coffee plantations in Colombia was sampled by a variety of methods and the species composition and density under the two systems compared. Twenty species of Lutzomyia sandflies (Diptera: Psychodidae: Phlebotominae) were collected, of which eight were found only in the 'Coffee Axis' ('Eje Cafetero') of the departments of Caldas, Risaralda and Quindio, six were exclusive to the department of Norte de Santander and six occurred in both regions. Four species were collected only in traditional plantations and two exclusively in intensified ones. At least 13 species occurred in both plantation types. Fifteen species are opportunistic man-biters and eight are suspected vectors of leishmaniasis caused by Le. braziliensis, Le. panamensis or Le. mexicana. Seven species were collected inside houses and may be involved in intradomiciliary transmission of Leishmania. The dominant species in Norte de Santander was Lu. spinicrassa, which made up 93.8% of all the sandflies collected in this department. This species was absent from the Eje Cafetero and a number of others among the 15 recorded there might be responsible for Leishmania transmission in this region, including Lu. trapidoi, Lu. yuilli, Lu. gomezi, L. hartmanni and Lu. ovallesi. Sandfly population densities were significantly higher in traditional plantations than in intensified ones. Residents of traditional plantations were able to describe sandflies in significantly more detail than those of intensified plantations, based on seven basic characteristics related to the appearance and biting behaviour of the insects.     

Comparison of carbon dioxide, octenol and a host-odour as mosquito attractants in the Upper Rhine Valley, Germany

ield studies were conducted in the Upper Rhine Valley to determine the responses of mosquitoes to CDC traps baited with either CO₂, octenol, light or paired combinations of these. Among eight mosquito species caught, the attractant effect on trap catches was studied in the four most abundant: Aedes vexans, Ae.rossicus, Ae.cinereus and Culex pipiens .
Traps baited only with light or octenol caught few mosquitoes, whereas many were caught by traps baited with CO₂ alone or in combination with either of the other candidate attractants. CO₂ baited traps, with or without light, caught the most Aedes . The combination of CO₂ and octenol attracted most Cx pipiens , but this apparent synergy was not significant.
Using a caged hamster compared to CO₂ as bait in a CDC light-trap with only intermittent fan suction, the hamster attracted less mosquitoes than CO₂ emitted at a rate of 225 g/h on days 1 and 2, whereas on days 3 and 4 the smell from the hamster's cage became significantly more attractive than this rate of CO₂ for all species of mosquitoes.     

Abundance of Lutzomyia ovallesi but not Lu. gomezi (Diptera: Psychodidae) correlated with cutaneous leishmaniasis incidence in north-central Venezuela

In north-central Venezuela Lutzomyia gomezi and Lu. ovallesi are the main endophilic/anthropophilic species of phlebotomine sandflies implicated as vectors of cutaneous leishmaniasis (CL). Lutzomyia ovallesi has been found infected with Leishmania braziliensis (1.2%) and less often with Le. mexicana (0.07%), while Le. braziliensis infections have also been found in Lu. gomezi (0.47%). We investigated population densities of these sandflies using two sampling methods with four series of collections between January 1991 and March 1995 at El Ingenio, Miranda State. All-night outdoor collections from a Shannon trap were correlated with indoor collections from CDC light–traps by linear regression, which proved to be statistically significant for both species. Estimated numbers of female sandflies per house per night were found to be proportional to monthly precipitation (i.e. rainfall), with a lag time of seven months for Lu. ovallesi and of six months for Lu. gomezi . Predominance of Lu. ovallesi over Lu. gomezi ( c. 10 :1 ) was observed throughout the year, with the number of infected females estimated as 0.043 ± 0.047 Lu. ovallesi and 0.0085 ± 0.0124 Lu. gomezi per CDC trap per house per night (ratio ∼ 5:1). The mean rate of new CL cases per house per year and sandfly abundance were correlated by linear regression, showing a statistically significant relationship for Lu. ovallesi but not for Lu. gomezi . The negative intercept indicated that, on average, the CDC trap density exceeds 800 Lu. ovallesi females/house/year before new CL cases occur at El Ingenio.     

How reliable are light traps in estimating biting rates of adult Anopheles gambiae s.l. (Diptera: Culicidae) in the presence of treated bed nets?

The sampling efficiency of light trap catches relative to human bait catches in estimating biting rates of the mosquito Anopheles gambiae Giles was investigated in two types of community in southern Sierra Leone: (i) where most of the inhabitants slept under treated bed nets; and (ii) where most of the inhabitants slept without bed nets. The number of female A. gambiae mosquitoes caught in these communities by light trap was strongly correlated (r > or = 0.72) with those from corresponding human biting catches performed either on the same or adjacent nights. It was found that the relative sampling efficiency of light traps varied slightly but significantly with mosquito abundance in villages with treated bed nets, but not in those without them. Nevertheless, the relationship between relative sampling efficiency and mosquito abundance did not differ significantly between the two types of village. Overall, there was insufficient evidence to show that the presence of treated nets altered the relative efficiency of light traps and any bias was only slight, and unlikely to be of any practical importance. Hence, it was concluded that light traps can be used as a surrogate for human bait catches in estimating biting rates of A. gambiae mosquitoes in the two communities.     

Comparison between anopheline mosquitoes (Diptera: Culicidae) caught using different methods in a malaria endemic area of Papua New Guinea

The mosquito sampling efficiency of CDC (Centers for Disease Control) miniature light traps hung adjacent to mosquito nets, was compared with that of both indoor and outdoor human-bait collections in ten villages in the Wosera area of Papua New Guinea. The most frequently collected anopheline in the matched indoor and light trap samples was Anopheles koliensis Owen, followed by A. punctulatus D?nitz, A. karwari (James), A. farauti Laveran (sensu lato), A. longirostris Brug and A. bancroftii Giles. All species were much less frequent in the light traps than in landing catches. The hypothesis that the numbers of mosquitoes in light traps are proportional to human landing catches was examined using regression models that allowed for sampling error in both entomological measurements. Light traps under-sampled A. punctulatus and A. farauti s.l. at high densities. The models indicated that the ratio of light trap to landing catch females of A. koliensis and A. karwari increased with increasing mosquito density. Light trap catches of A. longirostris were proportional to indoor landing rates but when outdoor landing rates were high this species was under-sampled by light traps. Numbers of A. bancroftii in light traps were found to be proportional to those in outdoor landing catches, but were negatively related to those attempting to bite indoors. Circumsporozoite positivity rates for both Plasmodium falciparum Welch and P. vivax (Grassi & Feletti) in A. punctulatus and A. farauti s.l. were significantly higher in light trap collections than in either indoor or outdoor landing catches, suggesting that light traps may selectively sample older mosquitoes of these species.     

Distribution of phlebotomine fauna (Diptera: Psychodidae) across an urban-rural gradient in an area of endemic visceral leishmaniasis in northern Brazil

The number of visceral leishmaniasis (VL) cases has increased over the past 10 years in Brazil, especially in the North and Northeast regions of the country. The aim of this study was to evaluate the urbanisation of VL vectors in Barcarena, Pará, an area in northern Brazil where VL is endemic. Sandflies were captured using Centers for Disease Control (CDC) light traps along an urban-rural gradient. The CDC traps were installed inside hen houses at a height of 150 cm. A total of 5,089 sandflies were collected and 11 species were identified. The predominant species was Lutzomyia longipalpis (rate of 95.15%), which suggests its participation in the transmission of VL. A total of 1,451 Lu. longipalpis females were dissected and no Leishmania infections were detected. Most of the sandflies were captured at the border of a forest (88.25%) and no flies were captured in the urban area, which suggests that transmission is still restricted to rural sites. However, the fact that a specimen was collected in an intermediate area indicates that urbanisation is a real possibility and that vector monitoring is important.     

Incrimination of four sandfly species previously unrecognized as vectors of Leishmania parasites in Mexico

Cutaneous leishmaniasis (CL) is endemic to the Yucatan Peninsula of Mexico. The main causative agent is the parasite Leishmania mexicana (Biagi) (Kinetoplastida: Trypanosomatidae) and, based on the classic work of Dr Biagi's research team, it has been generally accepted and frequently reported that the only vector of L. mexicana in the region is the sandfly Lutzomyia olmeca olmeca (Vargas & Diáz‐Nájera) (Diptera: Psychodidae). Evidence gathered from recent entomological studies conducted mainly in Calakmul, Campeche, however, suggests that other species may also be vectors of L. mexicana. We conducted a field study in two villages in Calakmul, Campeche in the Yucatan Peninsula, where recent cases of CL have been reported, to document the species composition and relative abundances of the sandfly fauna and to identify which species are likely to be the main vectors by assessing the biting rates and parasite infection rates of the suspected vector species. Sandfly catches were conducted from November 2005 to February 2006 in Unión 20 de Junio and Dos Lagunas Sur. Sandflies were captured using Shannon (18.00–22.00 hours), Disney and CDC light traps (18.00–06.00 hours). Biting and infection rates were calculated for the four most abundant species: Lutzomyia cruciata (Coquillett), Lu. o. olmeca, Lutzomyia panamensis (Shannon) and Lutzomyia shannoni (Dyar). In Dos Lagunas Sur, Lu. panamensis and Lu. o. olmeca exhibited the highest biting rates throughout the sampling period. In Unión 20 de Junio, Lu. cruciata and Lu. o. olmeca had the highest biting rates over the same period. Regarding infection rates, we report herein the establishment of a polymerase chain reaction protocol and validation of IR1 and LM17 oligonucleotides to analyse the infection rates of sandflies. Out of 769 females analysed, the overall infection rates were 1.4% in Dos Lagunas Sur and 5.3% in Unión 20 de Junio. In Dos Lagunas Sur we found L. mexicana infections in two sandfly species, Lu. shannoni and Lutzomyia ylephiletor (Fairchild & Hertig), whereas in Unión 20 de Junio we found infections in Lu. shannoni, Lu. cruciata, Lu. o. olmeca and Lu. panamensis. The possible role of these four sandfly species in relation to L. mexicana transmission in Calakmul is discussed.     

Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems

The composition and seasonal occurrence of sandflies were investigated in coffee agroecosystems in the Soconusco region of Chiapas, Mexico. Insect sampling was performed on three plantations located at different altitudes: Finca Guadalupe Zajú [1,000 m above sea level (a.s.l.)], Finca Argovia (613 m a.s.l.) and Teotihuacán del Valle (429 m a.s.l.). Sandflies were sampled monthly from August 2007-July 2008 using three sampling methods: Shannon traps, CDC miniature light traps and Disney traps. Sampling was conducted for 3 h during three consecutive nights, beginning at sunset. A total of 4,387 sandflies were collected during the course of the study: 2,718 individuals in Finca Guadalupe Zajú, 605 in Finca Argovia and 1,064 in Teotihuacán del Valle. The Shannon traps captured 94.3% of the total sandflies, while the CDC light traps and Disney traps captured 4.9% and 0.8%, respectively. More females than males were collected at all sites. While the number of sandflies captured was positively correlated with temperature and relative humidity, a negative correlation was observed between sandfly numbers and rainfall. Five species of sandflies were captured: Lutzomyia cruciata , Lutzomyia texana , Lutzomyia ovallesi , Lutzomyia cratifer / undulata and Brumptomyia sp. Lu. cruciata , constituting 98.8% of the total, was the most abundant species. None of the captured sandflies was infected with Leishmania spp.     

Development of an exposure-free bednet trap for sampling Afrotropical malaria vectors

An exposure-free bednet trap (the 'Mbita trap') for sampling of Afrotropical malaria vectors was developed during preliminary studies of mosquito behaviour around human-occupied bednets. Its mosquito sampling efficiency was compared to the CDC miniature light-trap and human landing catches under semi-field conditions in a screen-walled greenhouse using laboratory-reared Anopheles gambiae Giles sensu stricto (Diptera: Culicidae). When compared in a competitive manner (side by side), the Mbita trap caught 4.1+/-0.5 times as many mosquitoes as the CDC light-trap, hung beside an occupied bednet (P < 0.000 1) and 43.2+/-10% the number caught by human landing catches (P < 0.0001). The ratio of Mbita trap catches to those of the CDC light trap increased with decreasing mosquito density. Mosquito density did not affect the ratio of Mbita trap to human-landing catches. In a non-competitive comparison (each method independent of the other), the Mbita trap caught 89.7+/-10% the number of mosquitoes caught by human landing catches (P < 0.0001) and 1.2+/-0.1 times more mosquitoes than the CDC light trap (P = 0.0008). Differences in Mbita trap performance relative to the human landing catch under noncompetitive vs. competitive conditions were explained by the rate at which each method captured mosquitoes. Such bednet traps do not expose people to potentially infectious mosquito bites and operate passively all night without the need for skilled personnel. This trap is specifically designed to catch host-seeking mosquitoes only and may be an effective, sensitive, user-friendly and economic alternative to existing methods for mosquito surveillance in Africa.     

Monitoring oriental fruit moth (Lepidoptera: Tortricidae) with sticky traps baited with terpinyl acetate and sex pheromone

Studies in Argentina and Chile during 2010–2011 evaluated a new trap (Ajar) for monitoring the oriental fruit moth, Grapholita molesta (Busck). The Ajar trap was delta‐shaped with a jar filled with a terpinyl acetate plus brown sugar bait attached to the bottom centre of the trap. The screened lid of the jar was inserted inside the trap, and moths were caught on a sticky insert surrounding the lid. The Ajar trap was evaluated with and without the addition of a sex pheromone lure and compared with delta traps left unbaited or baited with a sex pheromone lure and a bucket trap filled with the same liquid bait. Studies were conducted in a sex pheromone‐treated orchard in Argentina and an untreated orchard in Chile. In Chile, the Ajar trap without the sex pheromone lure caught significantly fewer males, females and total moths than the bucket trap, and fewer males and more females than the sex pheromone‐baited delta trap. Total moth catch did not differ between the Ajar trap without a sex pheromone lure and the sex pheromone‐baited trap. Adding a sex pheromone lure to the Ajar trap significantly increased total moth catches to levels not different from those in the bucket trap. However, the Ajar trap with the sex pheromone lure caught significantly more males and fewer females than the bucket trap. In Argentina, the Ajar trap with or without the addition of a sex pheromone lure caught similar numbers of both sexes and total moths as the bucket trap. The sex pheromone‐baited delta trap caught <4% of the number of moths as these three traps. The bucket trap in both studies caught significantly more non‐targets than the delta and Ajar traps. Moth catches in the Ajar trap declined significantly after 2–3 weeks when the bait was not replaced.     

Sampling methods for phlebotomine sandflies

A review is presented of methods for sampling phlebotomine sandflies (Diptera: Psychodidae). Among approximately 500 species of Phlebotominae so far described, mostly in the New World genus Lutzomyia and the Old World genus Phlebotomus, about 10% are known vectors of Leishmania parasites or other pathogens. Despite being small and fragile, sandflies have a wide geographical range with species occupying a considerable diversity of ecotopes and habitats, from deserts to humid forests, so that suitable methods for collecting them are influenced by environmental conditions where they are sought. Because immature phlebotomines occupy obscure terrestrial habitats, it is difficult to find their breeding sites. Therefore, most trapping methods and sampling procedures focus on sandfly adults, whether resting or active. The diurnal resting sites of adult sandflies include tree holes, buttress roots, rock crevices, houses, animal shelters and burrows, from which they may be aspirated directly or trapped after being disturbed. Sandflies can be collected during their periods of activity by interception traps, or by using attractants such as bait animals, CO2 or light. The method of trapping used should: (a) be suited to the habitat and area to be surveyed, (b) take into account the segment of the sandfly population to be sampled (species, sex and reproduction condition) and (c) yield specimens of appropriate condition for the study objectives (e.g. identification of species present, population genetics or vector implication). Methods for preservation and transportation of sandflies to the laboratory also depend on the objectives of a particular study and are described accordingly.