Boric acid bait kills adult mosquitoes (Diptera: Culicidae)

The toxicity of boric acid solutions to adult Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, and Aedes albopictus Skuse was evaluated in the laboratory. Median lethal concentrations (LC50 in %) at 24-h exposure for male and female An. quadrimaculatus were 0.317 and 0.885, respectively; for Cx. nigripalpus, 0.273 and 0.560, respectively; and for Ae. albopictus, 0.174 and 0.527, respectively. The LC50 values at 48-h exposure for male and female An. quadrimaculatus were 0.101 and 0.395, respectively; for Cx. nigripalpus, 0.098 and 0.255, respectively; and for Ae. albopictus, 0.078 and 0.244, respectively. In laboratory tests, access for 48 h to sucrose (10%) water containing 1% boric acid (boric acid bait) resulted in 98% mortality in blood fed, gravid, and parous Ae. albopictus. When offered a choice between boric acid bait and sucrose water, 52% of male and 33% of female Ae. albopictus ingested sufficient boric acid bait in 24 h to cause death; after 48 h, respective percent mortalities were 88 and 58%. In outdoor tests, in a walk-in screened cage (156 m3) containing 1,250 female Ae. albopictus, mosquito biting rates on the exposed forearm of a human subject in 3-min exposure were reduced > or = 78% for the boric acid bait treatment, compared with a sucrose water control.     

Checklist of Iranian mosquitoes (Diptera: Culicidae).

The mosquito fauna of Iran includes seven genera, 64 species, and three subspecies. The records of 12 other species should be verified. There are 24 species in the most recent checklist of Iranian Anopheles. Two species, An. peditaeniatus and An. fluviatilis species V, have been reported since. An. atroparvus, An. labranchiae, and An. martinius of the Maculipennis Group, and An. cinereus, An. nigerrimus, and An. rhodesiensis rupicola were recorded previously but are not included in the checklist. The checklist of Iranian Culicinae includes ten species of the tribe Aedini, but there are some records of four other species: Aedes aegypti, Ochlerotatus berlandi, Oc. chelli, and Oc. dorsalis. The genus Culex includes 19 species, excluding Cx. impudicus, which has not been collected recently, and some doubtful records of Cx. univittatus, Cx. vishnui, and Cx. vagans. The genus Culiseta includes five species and the genera Coquillettidia and Uranotaenia each include one species in Iran. No information is available for the An. subpictus, Oc. caspius, Oc. detritus, and Oc. pulcritaris species complexes in Iran. The An. claviger and Cx. pipiens complexes and the An. hyrcanus group require review.     

New investigation technique for thoracic sclerites of mosquitoes (Diptera, Culicidae) for the correct identification of genera and species

A new technique for studying the external morphology of thoracic sclerites of mosquitoes (Diptera: Culicidae) was developed. According to this method, the shape of sclerites and the position of setae and scales can be examined using SEM or light microscopy even in cases when setae or scales have been lost. The method can be recommended for the damaged material which is often obtained during sampling. The bases of setae usually exceed 100 μm in diameter and thus differ significantly from the bases of scales which are about 30 μm in diameter. Analysis of the structure of sclerites and the arrangement of setae and scales on them in different specimens of one species may reveal intraspecific variation of this character complex. Comparison of species from different genera of the family Culicidae, as well as comparison of closely related species, will probably help to estimate the diagnostic value of thoracic sclerites as morphological characters.     

An annotated list of the mosquitoes (Diptera: Culicidae) of Mississippi

There has been no previous systematic statewide study of mosquitoes in Mississippi. This survey, resulting in the collection of over 400,000 specimens, was conducted by the authors from 2003 to 2007 throughout much of the state using CO₂‐baited CDC light traps and larval dipping. In addition, a health department contract mosquito surveillance technician collected several thousand specimens from the state from 2001 to 2003. Lastly, specimens housed at the Mississippi State University Entomological Museum, obtained from previous surveys, were included as vouchers for species occurring in the state. The collection records and literature show 60 species as occurring or having occurred in Mississippi. Voucher specimens representing 57 of the 60 species discussed are deposited in the Mississippi Entomological Museum or in the U.S. National Museum of Natural History (USNM), Washington, D.C.     

Landscape and zonal distribution of bloodsucking mosquitoes and horseflies (Diptera: Culicidae,Tabanidae) in the northeastern Russian Plain

Analysis of landscape and zonal changes in the species diversity and abundance of 34 species of bloodsucking mosquitoes and 42 species of horseflies in the northeastern Russian Plain was carried out. The species diversity of both families is reduced from south to north. Two steps of faunistic depletion can be revealed: at the boundary of the middle and northern taiga (both mosquitoes and horseflies) and at the boundary of the extreme northern taiga and the forest-tundra (horseflies only). Species whose northern and southern distribution boundaries lie within the territory studied are listed.     

Global diversity of mosquitoes (Insecta: Diptera: Culicidae) in freshwater

Mosquitoes that inhabit freshwater habitats play an important role in the ecological food chain, and many of them are vicious biters and transmitters of human and animal diseases. Relevant information about mosquitoes from various regions of the world are noted, including their morphology, taxonomy, habitats, species diversity, distribution, endemicity, phylogeny, and medical importance. Guest editors: E. V. Balian, C. Lévêque, H. Segers and K. Martens Freshwater Animal Diversity Assessment     

Comparative morphology of the pyloric armature of adult mosquitoes (Diptera: Culicidae)

The structure of the pyloric armature, hypothesized to aid in blood-meal digestion or parasite resistance, was compared quantitatively among the following 8 species in 5 genera of adult mosquitoes from the southeastern United States: Aedes albopictus, Aedes japonicus, Aedes triseriatus, Anopheles punctipennis, Culex pipiens s.l., Culex restuans, Orthopodomyia signifera, and Toxorhynchites rutilus. Females differed significantly among species in the structure of spines composing the armature, with Aedes spp. forming one general group, Culex spp. another, and An. punctipennis and Or. signifera a third. Relationships of species based on structural characters of the armature were consistent with recent culicid phylogenies. Although pyloric armature has been noted in mosquitoes and other insects, this is the first quantitative investigation of the mosquito pyloric armature.     

An annotated checklist of the Anopheles mosquitoes (Diptera: Culicidae) in Iran.

An annotated checklist of the Anopheles mosquitoes in Iran is provided. The list is based on data contained in Iranian manuals and reports and information published elsewhere. Supplementary information is provided for 24 species.     

The mosquitoes (Diptera: Culicidae) in Maliuc (Danube delta)--faunistical and ecological data

The paper reports the results of the survey of the mosquito fauna in the Maliuc area (Danube delta) in 1983-1985. 16 mosquito species have been recorded in the area during the investigations: Anopheles maculipennis--complex, An. hyrcanus, Uranotaenia unguiculata, Coquillettidia richiardii, Culiseta annulata, Aedes vexans, Ae. cinereus, Ae. caspius, Ae. dorsalis, Ae. excrucians, Ae. flavescens, Ae. leucomelas, Ae. intrudens, Culex pipiens, C. martinii, Cx. modestus. They have been captured by light traps, on human bait, with entomological hand net and within an indoor resting site (building). Six types of habitats of adult mosquitoes, taking into account the characteristics of the soil and vegetation have been identified in the area. The quantitative and qualitative differences of the mosquito fauna within these six habitats have been recorded. Also, the suitable capture methods within every habitat have been established.     

Gynandromorphs in mosquitoes (Diptera: Culicidae) from Valle del Cauca, Colombia

Gynandromorphs of Culex nigripalpus Theobald (2), Cx. pedroi Sirivanakarn and Belkin (1) and Aedes albopictus (Skuse) (2) are described. Two individuals of the latter species were reared in the laboratory, while the remaining three specimens were wild-caught with different traps in rural areas in Valle del Cauca department, southwestern Colombia. All of the individuals were mounted on microscopic slides with Canada balsam. From each mosquito, main morphological characteristics are described and illustrated. Due to the paucity of information about this subject, these findings as well as other relevant cases are discussed.     

Tires as larval habitats for mosquitoes (Diptera: Culicidae) in southern Manitoba, Canada

In 2003, a survey at waste management grounds and tire dealerships was conducted to determine the species composition of mosquitoes in tires in southern Manitoba, Canada. Over 25% of the 1,142 tires sampled contained a total of 32,474 mosquito larvae and pupae. Culex restuans made up at least 95% of the larvae collected for each month of the summer. Culiseta inornata and Culex tarsalis reached their greatest numbers in July and August, respectively, though they were never abundant. Ochlerotatus triseriatus was also found but never reached more than 1% of the total larvae collected in any given month. Mosquito prevalence was more than three times greater in August (36.1%) than in June (11.7%). Orientation affected prevalence of mosquitoes in tires: 31.4% of vertical tires (tires standing on their treads) contained mosquitoes, whereas mosquitoes were found in only 18.9% of horizontal tires (tires parallel to the ground). Tires in the eastern region of Manitoba contained mosquitoes more often (61.7%), irrespective of date, than Winnipeg (25.9%), the central region (29.1%), or the western region (19.8%). Mosquito prevalence was similar across three size categories of tires, car tires (18.8%), truck tires (19.8%), and semi-trailer tires (26.7%), though tractor tires (47.8%) contained significantly more mosquitoes than tires in the other categories.     

The distribution of mosquitoes (Diptera,Culicidae) in the Republic of Azerbaijan

The mosquito fauna in the territory of the Republic of Azerbaijan comprises 24 species from 7 genera. The dominant species are Anopheles sacharovi, Culex pipiens, Aedes caspius, and Ae. geniculatus in the forest area, and Coquillettidia richiardii in the lowlands, where there are swamps overgrown with reeds.     

Predation potential of three flatworm species (Platyhelminthes: Turbellaria) on mosquitoes (Diptera: Culicidae)

We conducted a field survey for flatworms to select species as potential biological control agents against Aedes aegypti and Culex pipiens (Diptera, Culicidae) breeding in artificial containers. Laboratory experiments were performed to determine the daily predation rate, differential predation on each mosquito larval instar, selective predation on either A. aegypti or C. pipiens, and predator tolerance to water from artificial containers. Girardia anceps (Tricladida, Paludicola, Dugesiidae), Mesostoma ehrenbergii and Bothromesostoma cf. evelinae (Rhabdocoela, Typhloplanoida, Typhloplanidae) were found in temporary puddles and permanent pools. In the laboratory, they killed between 52% and 100% of immature mosquitoes coexisting in the same habitat. No preference of flatworms for mosquito preys was detected. Predation rate was related to predator size and instar of preys. Girardia anceps and B. evelinae survived after a dry period and when re-flooding occurred, they laid eggs. Tolerance to water from artificial containers was highest in G. anceps and this species could be a suitable predator to reduce mosquito populations from artificial containers using an inoculative approach.     

Utility of the white gene in estimating phylogenetic relationships among mosquitoes (Diptera: Culicidae)

The utility of a nuclear protein-coding gene for reconstructing phylogenetic relationships within the family Culicidae was explored. Relationships among 13 species representing three subfamilies and nine genera of Culicidae were analyzed using a 762-bp fragment of coding sequence from the eye color gene, white. Outgroups for the study were two species from the sister group Chaoboridae. Sequences were determined from clone PCR products amplified from genomic DNA, and aligned following conceptual intron splicing and amino acid translation. Third codon positions were characterized by high levels of divergence and biased nucleotide composition, the intensity and direction of which varied among taxa. Equal weighting of all characters resulted in parsimony and neighboring-joining trees at odds with the generally accepted phylogenetic hypothesis based on morphology and rDNA sequences. The application of differential weighting schemes recovered the traditional hypothesis, in which the subfamily Anophelinae formed the basal clade. The subfamily Toxorhynchitinae occupied an intermediate position, and was a sister group to the subfamily Culicinae. Within Culicinae, the genera Sabethes and Tripteroides formed an ancestral clade, while the Culex-Deinocerites and Aedes- Haemagogus clades occupied increasingly derived positions in the molecular phylogeny. An intron present in the Culicinae- Toxorhynchitinae lineage and one outgroup taxon was absent in the basal Anophelinae lineage and the second outgroup taxon, suggesting that intron insertions or deletions may not always be reliable systematic characters.      

Phylogeny of mosquitoes of tribe Culicini (Diptera: Culicidae) based on morphological diversity

Harbach, R. E., Kitching, I. J., Culverwell, C. L., Dubois, J. & Linton, Y.‐M. (2012). Phylogeny of mosquitoes of tribe Culicini (Diptera: Culicidae) based on morphological diversity. —Zoologica Scripta, 41, 499–514. Relationships among taxa of the mosquito tribe Culicini are explored using 169 morphological characters from 86 exemplar species representing the four genera and 26 subgenera of Culicini, most species groups and subgroups of subgenus Culex and an outgroup of five species from five other tribes. We analysed the data set, with multistate characters treated as unordered, under implied weights with values of K ranging from 1 to 20, implemented by TNT. Each analysis, except K = 4, produced a single most parsimonious (fittest) cladogram (MPC). The topology of the ingroup was identical for K = 6–11, whereas the MPCs for K = 14–20 differed only in the position of a single species, which occupied the same position in the K = 16 and K = 6–11 topologies. The K = 9 and K = 16 trees were given further consideration. In both these cladograms, Lutzia is sister to a clade comprising genera Culex, Deinocerites and Galindomyia. The two topologies have 13 clades in common, but their arrangements differ primarily because of Culex (Culex) duttoni acting as a ‘rogue’ taxon. We evaluated the effect of removing this species from the K = 9 and K = 16 analyses and chose the refined K = 9 topology as the best hypothesis of relationships within Culicini. Genus Culex is not monophyletic because it includes Deinocerites and Galindomyia as derived members of the New World subgenera. With the exception of subgenera Culex, Eumelanomyia and Neoculex, there is strong support for the monophyly of all genera and subgenera. Subgenus Culex would be monophyletic were four other subgenera included and three other taxa (the Afrotropical Cx. duttoni, Neotropical Cx. apicinus and the Australasian Atriceps Group) excluded.