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West Nile Virus (WNV) first arrived in Ontario, Canada in 2001 and has since spread throughout most of the province, causing disease in humans. The provincial government established a province-wide surveillance program to monitor WNV transmission throughout the 36 regional health units. Here we have acquired records of WNV human and mosquito surveillance from 2002 to 2013 to describe seasonal and geographic trends in WNV activity in southern Ontario. Additionally, we obtained climate data from seven municipalities to investigate how temperature and precipitation affect WNV transmission dynamics. We identified a strong quadratic relationship between the number of confirmed human cases and positive Culex mosquito pools recorded at the end of each year (R2 = 0.9783, p < 0.001). Using Spearman rank correlation tests, we identified that the minimum infection rate of Culex pipiens/restuans pools are the strongest predictor of human cases at a 1 week lag period. We also identified positive correlations between minimum infection rates, temperature, vector abundance, and cumulative precipitation. Global Moran's I index indicates strong positive autocorrelation and clustering of positive Culex pool counts in southern Ontario. Local indicators of spatial association tests revealed a total of 44 high-high and 1 high-low trap locations (n = 680). In the current work we have identified when and where hot spots of WNV activity have occurred in southern Ontario. The municipalities surrounding the western shore of the Lake Ontario and Windsor-Essex County have the largest records of positive mosquitoes and human cases. We identified that positive mosquitoes are a strong indicator of human cases to follow in the coming weeks. An epidemic action threshold of cumulative positive Culex pools was established, allowing Ontario public health officials to predict an epidemic at epidemiological week 34 (rho = 0.90, p < 0.001). These data have the potential to contribute to more efficient larvicide programs and awareness campaigns for the public.

Background Several recent climate change reviews have stressed the possibility of some malaria vectors occupying regions of higher altitudes than previously recorded. Indeed, highland malaria has been observed in several African nations, possibly attributable to changes in land use, vector control and local climate. This study attempts to expand the current knowledge of the distribution of common Anopheles species in Ecuador, with particular attention to highland regions (> 500 m) of the Andes. Methods Extensive field collections of larvae were undertaken in 2008, 2009 and 2010 throughout all regions of Ecuador (except the lower-altitude Amazonian plain) and compared to historical distribution maps reproduced from the 1940s. Larvae were identified using both a morphological key and sequencing of the 800 bp region of the CO1 mitochondrial gene. In addition, spatial statistics (Getis-Ord Hotspot Analysis: Gi*) were used to determine high and low-density clusters of each species in Ecuador. Results Distributions have been updated for five species of Anopheles in Ecuador: Anopheles albimanus , Anopheles pseudopunctipennis , Anopheles punctimacula , Anopheles eiseni and Anopheles oswaldoi s.l .. Historical maps indicate that An. pseudopunctipennis used to be widespread in highland Andean valleys, while other species were completely restricted to lowland areas. By comparison, updated maps for the other four collected species show higher maximum elevations and/or more widespread distributions in highland regions than previously recorded. Gi* analysis determined some highland hot spots for An. albimanus , but only cold spots for all other species. Conclusions This study documents the establishment of multiple anopheline species in high altitude regions of Ecuador, often in areas where malaria eradication programs are not focused.

Abstract Coquillettidia perturbans (Walker) is a North American mosquito species of medical and veterinary importance that has been implicated as a vector of eastern equine encephalitis virus. Larval and pupal C. perturbans possess highly specialized respiratory appendages that enable them to respire from air vesicles in the hollow roots and shoots of emergent aquatic vegetation, which means that the larval and pupal stages have remained largely understudied. Field-collected C. perturbans larvae, pupae, and adults were studied under laboratory conditions in an attempt to establish a laboratory colony. Blood-fed adults successfully laid egg rafts in containers provisioned with water hyacinth plants (Pontederia crassipes). Larvae and pupae were maintained on hydroponically grown wheat seedlings (Triticum sp.). Images and descriptions of egg rafts, larvae, and pupae are provided with special reference to hatch success, larval instar traits and pupal trumpet morphology.

The purpose of this study was to establish geospatial and seasonal distributions of West Nile virus vectors in southern Ontario, Canada using historical surveillance data from 2002 to 2014. We set out to produce mosquito abundance prediction surfaces for each of Ontario’s thirteen West Nile virus vectors. We also set out to determine whether elevation and proximity to conservation areas and provincial parks, wetlands, and population centres could be used to improve our model. Our results indicated that the data sets for Anopheles quadrimaculatus, Anopheles punctipennis, Anopheles walkeri, Culex salinarius, Culex tarsalis, Ochlerotatus stimulans, and Ochlerotatus triseriatus were not suitable for geospatial modelling because they are randomly distributed throughout Ontario. Spatial prediction surfaces were created for Aedes japonicus and proximity to wetlands, Aedes vexans and proximity to population centres, Culex pipiens/restuans and proximity to population centres, Ochlerotatus canadensis and elevation, and Ochlerotatus trivittatus and proximity to population centres using kriging. Seasonal distributions are presented for all thirteen species. We have identified both when and where vector species are most abundant in southern Ontario. These data have the potential to contribute to a more efficient and focused larvicide program and West Nile virus awareness campaigns.

We provide an updated checklist of 67 endemic mosquito species known from Ontario, Canada. Nine endemic species are added to the checklist found in Darsie and Ward (2005): Aedes cantator, Ae. churchillensis, Ae. nigripes, Ae. pullatus, Anopheles perplexens, An. crucians, An. smaragdinus, Culex erraticus, and Cx. salinarius. Only 4 specimens of Ae. albopictus have been recorded in Ontario since 2001 despite concerted efforts to find this species; therefore, it is considered an “accidental” species and is excluded from the checklist.

Recent collection data indicate that at least four potential malaria vectors occupy more widespread distributions within the Andean highlands than in the past. Since habitat elimination is an important aspect of malaria control, it is vital to characterize larval habitats for Anopheles species within both lowland and highland sites. To that end, 276 sites within Ecuador were surveyed between 2008 and 2010. Characteristics of Anopheles-present sites for four species were compared to Anopheles-absent sites within the same geographical range and also to Anopheles-absent sites within a highland range representing potential future habitats. Thermochron iButtons© were used to describe the daily temperature variation within a subset of potential habitats. Anopheles albimanus (W.) was positively associated with permanent habitats, sand substrates, floating algae (cyanobacterial mats), and warmer temperatures in both comparisons. Anopheles pseudopunctipennis (T.) was associated with floating algae (cyanobacterial mats), warmer temperatures, and higher water clarity in both comparisons. Anopheles punctimacula (D.&K.) was negatively associated with floating algae and positively associated with dissolved oxygen in both comparisons. Anopheles oswaldoi s. l. (P.) was not significantly associated with any parameters more often than expected given larval-absent sites. The results indicate that minimum water temperatures might limit the upper altitudinal distribution of An. albimanus (18.7° C) and An. pseudopunctipennis (16.0° C).

The large carpenter bees nest in reeds, stems and wood. Many other Hymenoptera, including many wasps and some bees, have strong associations between the physical elements of their nests and behavior. Nests of the North American carpenter bee, Xylocopa virginica, were collected in southern Ontario. Nest architecture elements were examined with respect to their impact on life-history elements. In particular, it was determined that the brood cells are provisioned sequentially both within and among branches. There was also no detectable pattern of sex allocation in broods. Nests with branched architecture contained more foundresses, but these foundresses did not appear to contribute in the construction of larger nests. These findings are discussed with respect to other bees, and to the social structure of Xylocopa virginica.

The black fly subgenus Inseliellum is present on a series of archipelagos in the South Pacific. In this study, larval polytene chromosome maps of six Inseliellum species are presented. Chromosomal relationships among taxa were determined through shared fixed inversions or chromosomal landmark positioning. Three fixed inversions (IL-2, IIS-1, and IIIS-1) were shared among species, as was the position of the nucleolar organizer (NO) (IL or IIL). Comparisons to two previously studied species of Inseliellum are included to produce a cytological transformation series among eight taxa. The NO position defines two clades in the phylogeny of Inseliellum, herein named the NO-IL and NO-IIL clades. The utility of this cytological data set is discussed.

The polytene chromosome banding pattern of Simulium exasperans (Craig, 1987) is described for the first time. Three populations of S. exasperans from Moorea and Tahiti were examined cytologically. Interspecific comparisons revealed that S. exasperans is homosequential in chromosomal banding pattern to Simulium cataractarum (Craig, 1987), but contains three species-characteristic floating inversions: IL-1 ex .2 ex , IIL-1 ex ,2 ex , and IIIL-1 ex . No sex-linked inversions were identified; males and females had undifferentiated sex chromosomes. The IIL-1 ex ,2 ex inversion was in Hardy-Weinberg disequilibrium in two of the three populations. From this preliminary data, two cytotypes may exist: cytotype A (Belvedre Cascade population) and cytotype B (1st Afareaitu Cascade and Jardin Public Vaipahi populations). Contrary to phylogenetic and biogeographic data, it is hypothesized that the Belvedre Cascade population (cytotype A) is ancestral to the populations containing cytotype B. Furthermore, a heterozygote advantage may exist in cytotype B.

Simulium craigi Adler and Currie is a polymorphic species based on polytene chromosome banding patterns in the long arm of chromosome III (IIIL). Three cytotypes are described based on the predominant IIIL sequences. These correspond to three broad geographic areas: cytotype 'CC' from Pennsylvania; cytotype 'AF' from Ontario and Manitoba; and cytotype 'ACF/BCF' from New Hampshire. In the absence of sympatric populations, these cytotype differences are best explained by clinal variation within a single species. The relationship of S. craigi to other described members of the S. vernum group is discussed.