We describe and illustrate for the 1st time the pupa and larva of adult female Ficalbia ichiromiyagii based on specimens collected from a swamp forest in Otomi, Iriomote Island, Ryukyu Archipelago, Japan. The pupa has a trumpet that is 6.25 times its breadth at halfway, with a long meatal cleft line; setae 6-I, II considerably long, usually single or bifid; median caudal seta absent; and paddle edge serrated only on the outer apical half. The larva is characterized by dark pigmentation of the head and siphon, seta 1-C elongate and spiniform, usually with a short lateral spine on the inner basal side and siphon with 1 pecten spine and conspicuous seta 1-S at the base. The immature stages were found only in undisturbed jungle swamps with dense vegetation.

The overwintering ecology of Culiseta melanura was studied in a seasonally flooded evergreen forest swamp in south central Connecticut in an effort to clarify which larval stages successfully overwinter in the northeastern USA, and to determine the degree to which larval development and/or mortality occur during the winter months. A total of 8,626 immature Cs. melanura were collected weekly for analysis from subterranean crypts and cavities located under the roots of trees from December 13, 2011 to May 31, 2012. Despite the formation of ice on the surface water at the entrance holes to the crypts, water temperatures within the cavities remained above freezing (average  =  1.8°C) throughout the coldest winter months of January and February. A heterogeneous population of 2nd, 3rd, and 4th instars were recovered throughout the winter and early spring in the same relative proportions (30%, 30%, 40%, respectively), with no significant change in their comparative abundance during this period, providing unequivocal evidence that all 3 instars successfully overwinter in the region. Findings further demonstrate that larvae undergo no development during the winter and do not appear to be impacted by any measurable mortality. The cessation of larval diapause and a resumption of development was observed in mid-April and was coincident with a gradual increase in water temperature within the crypts to 9°C, in agreement with a previously calculated developmental thermal minimum of 8.5°C for Cs. melanura. This resulted in a protracted period of pupation that encompassed a minimum of 5 wk, followed by a staggered emergence of adults and an overlap of the residual overwintering population with larvae of the 1st summer generation.

In this study, we explore the potential of a commercially available mechanical mosquito control device, the Liberty Plus Mosquito Magnet® (hereafter referred to as Mosquito Magnet), to reduce the abundance of adult nuisance mosquito populations in public recreational areas. Mosquitoes were trapped on 2 replicate sites close to a campground at Brae Island Regional Park near Fort Langley, British Columbia, Canada. Each site comprised a treatment (Mosquito Magnets used) and control subsection (Mosquito Magnets not used). Mosquito numbers were assessed before and after the treatment period in both subsections at each site with Centers for Disease Control and Prevention (CDC) black light traps. Although nearly 200,000 mosquitoes from 14 different species were collected over 366 trap-nights from May 31 to July 31, 2008, the majority of those identified were Aedes sticticus (68%) and Ae. vexans (22%)—2 of the most notorious nuisance mosquito species in British Columbia. The number of mosquitoes captured by CDC black light traps increased overall during the study period due to natural seasonal variation. Nevertheless, a significant treatment effect (P  =  0.0389) was associated with an average decrease of about 32% in the average number of adult mosquitoes collected per day. These results strongly suggest that Mosquito Magnets can reduce the abundance of nuisance mosquitoes, potentially reducing the biting pressure on the public, and providing another tool in mosquito control operations.

A field bioassay evaluating candidate chemicals as aerial repellents was developed and evaluated against natural mosquito populations in Beltsville, MD. The bioassay consisted of an attractive source surrounded by a grid of 16 septa containing a volatile candidate aerial repellent, compared with an attractive source without such a grid. The attractive source was a Centers for Disease Control and Prevention light trap supplemented with carbon dioxide. Significant sources of variation included weather, position, and the differential response of mosquito species. Despite these sources of variation, significant repellent responses were obtained for catnip oil, E,Z-dihydronepetalactone, and DEET.

Seven mosquito species are recorded for the 1st time for northeastern Argentina: Culex (Melanoconion) albinensis, Cx. (Mel.) elevator, Cx. (Mel.) intrincatus, and Cx. (Mel.) serratimarge for Formosa Province, and Sabethes (Peytonulus) undosus, Sa. (Sabethinus) melanoninphe, and Toxorhynchites (Lynchiella) theobaldi for Chaco Province. The geographical distribution of these species is extended to northeastern Argentina, and the number of species increases to 97 and 75 for the provinces of Chaco and Formosa, respectively.

Throughout the early entomological campaigns in French Guiana (1900–1945), the presence of members of the Anopheles albitarsis Complex was reported in many places across the territory. However, since then no specimen has been caught despite many entomological studies conducted on the littoral and along the main rivers in places where malaria was endemic. We report here the 1st catches in the modern period of specimens of the An. albitarsis Complex in the deep rainforest. During a military intervention, Mosquito-Magnet® traps and the Centers for Disease Control and Prevention light traps were used to sample malaria vectors in an illegal gold mining area and a permanent checkpoint. Members of the An. albitarsis caught were molecularly identified using DNA barcoding. In the 2 sites where An. albitarsis s.l. were caught, all specimens were An. marajoara. As An. marajoara is considered as an important malaria vector in Amazonia, the highest interest must be shown to this species in French Guiana.

Culex molestus is an obligatory autogenous mosquito that is closely associated with subterranean habitats in urban areas. The objective of our study was to investigate the influence of larval and adult nutrition on the role of males in determining the expression of autogeny in Cx. molestus. Mosquitoes raised at low and high larval diets had sex ratio, wing length, mating rates, autogenous egg raft size, and hatching rates recorded. There was a higher ratio of males to females when raised at a low larval diet. Mean wing lengths of both males and females were significantly greater when raised at the high larval diet regime. Regardless of larval or adult diet, males mated with only a single female. Mosquitoes raised at the higher larval diet regimes developed significantly more autogenous eggs. However, the egg raft size was reduced when adult females were denied access to sugar. The results of this study indicate that the performance of males in the reproductive process is influenced by both larval diet and adult sugar feeding.

Using in vitro bioassays, we evaluated the crude methanol, ethanol, chloroform, and acetone leaf extracts of Artemisia annua as well as pure artemisinin against late 3rd and early 4th instars of Culex quinquefasciatus and Cx. tritaeniorhynchus. Based on the lethal concentration for 50% mortality (LC₅₀) and lethal concentration for 90% mortality (LC₉₀) values, the chloroform leaf extract was the most toxic, followed by methanol, ethanol, and acetone. The LC₅₀ and LC₉₀ values for chloroform extract were 0.18 and 9.65 ppm against Cx. quinquefasciatus and 0.91 and 8.73 ppm against Cx. tritaeniorhynchus, respectively. The LC₅₀ and LC₉₀ values for artemisinin, dissolved in chloroform, were significantly higher, 14.31 and 296.39 ppm for Cx. quinquefasciatus and 4.13 and 50.36 ppm for Cx. tritaeniorhynchus, respectively.

Field trials were conducted to demonstrate the need for correcting sampled spray concentration data for sampler collection efficiencies and estimated spray exposure levels in mosquito bioassays for cage interference effects. A large spray block was targeted with aerial spray treatments of etofenprox in order to create a gradient in both spray concentration and mortality. Spray concentrations were measured using rotary impactors, which were coupled with caged bioassays. Measured spray concentrations were corrected for sampler collection efficiencies, which ranged from 55% to 15%. The corrected spray concentrations were then used to estimate the spray levels inside the bioassay cages. Given the cage type used (Townzen type) and wind speeds occurring during the spray trials (2–4 m/sec), concentrations inside of the bioassay cage ranged from 65% to 68% of that measured within the spray block. Not correcting for the combination of sampler collection efficiency and cage interference, underestimated spray concentration levels inside the cages were 76–90%. Correcting field-measured data allows not only better comparisons between differing studies, but can also provide better estimates of caged insect mortality versus actual spray concentration exposure levels.

Insecticide resistance to organophosphates and carbamates can be the result of changes in acetylcholinesterase activity conferred by the ACE-1 mutation. Detection of this altered target site mutation is important in guiding informed decisions for resistance management. In this study we compared a competitive enzyme assay with a polymerase chain reaction assay utilizing a restriction enzyme. Both assays detected the ACE-1 mutation in Culex quinquefasciatus and agreement was 100%. The costs and benefits of each assay are presented.

We compared the differential display of Aedes albopictus cells, both resistant and susceptible to Bacillus thuringiensis israelensis (Bti), using differentially displayed reverse transcription polymerase chain reaction. We found 1 band about 200 base pairs long. After cloning and sequencing, the differentially expressed gene was similar to some partial messenger ribonucleic acid of Ae. aegypti, Culex quinquefasciatus, and Anopheles gambiae, rather than Ae. albopictus. This will be of some value for clarifying the mechanism of mosquito resistance to Bti products.

A new technique is described here to count mosquitoes using open-source software. We wanted to develop a protocol that would estimate the total number of mosquitoes from a picture using ImageJ. Adult mosquitoes from CO₂-baited traps were spread on a tray and photographed. The total number of mosquitoes in a picture was estimated using various calibrations on ImageJ, and results were compared with manual counting to identify the ideal calibration. The average trap count was 1,541, and the average difference between the manual count and the best calibration was 174.11 ± 21.59, with 93% correlation. Subsequently, contents of a trap were photographed 5 different times after they were shuffled between each picture to alter the picture pattern of adult mosquitoes. The standard error among variations stayed below 50, indicating limited variation for total count between pictures of the same trap when the pictures were processed through ImageJ. These results indicate the software could be utilized efficiently to estimate total number of mosquitoes from traps.

We have been using BG-Sentinel™ (BGS) traps to monitor populations of Aedes albopictus as part of an area-wide project for management of this species. Although BGS traps are very effective for collecting adult Ae. albopictus, the device is expensive and must be properly maintained to be effective. The trap also poses a challenge for mosquito control personnel because secure locations free from the risk of vandalism or pet damage during surveillance efforts are scarce. Additionally, acquiring access to private property or finding suitable shaded habitats to place traps can be difficult. Here we summarize a protocol for BGS trap surveillance of Ae. albopictus in a highly urbanized environment during an active mosquito season.

Duet™ was field evaluated against caged Aedes albopictus, with the use of a truck-mounted ultra-low volume (ULV) cold aerosol sprayer at the rate of 90.6 ml/ha. Cages were placed in 3 rows stationed 30.5, 61.0, and 91.5 m downwind of the spray vehicle. Initial knockdown was >99% with mortality ranging between 95.8% and 98.0% across the distances. Volume median diameter (VMD) and droplet density were slightly reduced (16.4% and 18.6%, respectively) by distance. Reduction in VMD and droplet density, however, did not reduce mortality. The ULV application of Duet is an effective adulticide against Ae. albopictus and may be a useful tool for use in mosquito abatement programs.

A Pioneer Eco-Backpack™ electric cold ultra-low volume (ULV) sprayer and a gas-powered Twister XL™ 3950 series 2 motorized knapsack ULV sprayer with Aqualuer® (20.6% permethrin AI) were evaluated against caged adult Aedes albopictus and Culex quinquefasciatus in St. Augustine, FL. The Pioneer Eco-Backpack sprayer provided 100% knockdown of both species of mosquitoes at 15 min; the Twister XL backpack sprayer resulted in 17–23% knockdown at 15 min. Both backpack sprayers with Aqualuer resulted in 100% mortality of both species at 24 h. The new Pioneer Eco-Backpack sprayer powered by electricity could be a potential tool for mosquito control.