RESUMEN
The mosquito species Aedes (Ochlerotatus) coluzzii Rioux, Guilvard & Pasteur, 1998 was distinguished from its sibling species Aedes detritus (Haliday, 1833) using an isoenzymatic method that required the destruction of the entire specimen, therefore no holotype was designated by the species authors. We aimed to designate a neotype for Ae. coluzzii from specimens collected from the type-locality and individually reared up to adult stage. Genomic DNA was extracted from pupal exuvia and ITS2 was sequenced, enabling verification of the identity of each specimen as Ae. coluzzii or Ae. detritus. Among the series of Ae. coluzzii, a male was designated as neotype and deposited in a collection. To our knowledge, this is the first time the type of a mosquito species is deposited thanks to its molecular identification from its pupal exuvia. The set of identified specimens allowed additional phylogenetic and morphologic studies.
Title: Utilisation d'une exuvie nymphale pour désigner le néotype intact d'une espèce appartenant à un complexe d'espèces jumelles - le cas d'Aedes coluzzii (Diptera, Culicidae). Abstract: L'espèce de moustique Aedes (Ochlerotatus) coluzzii Rioux, Guilvard & Pasteur, 1998 a été distinguée de son espèce jumelle Aedes detritus (Haliday, 1833) par une méthode isoenzymatique qui a nécessité la destruction de l'ensemble du spécimen, et donc aucun holotype n'a été désigné par les auteurs de l'espèce. Notre objectif était de désigner un néotype pour Ae. coluzzii à partir de spécimens collectés dans la localité-type et élevés individuellement jusqu'au stade adulte. L'ADN génomique a été extrait de l'exuvie nymphale et l'ITS2 a été séquencé, permettant la vérification de l'identité de chaque spécimen comme Ae. coluzzii ou Ae. détritus. Parmi la série d'Ae. coluzzii, un mâle a été désigné comme néotype et déposé dans une collection. À notre connaissance, c'est la première fois que le type d'une espèce de moustique est déposé grâce à l'identification moléculaire à partir de son exuvie nymphale. L'ensemble des spécimens identifiés a permis des études phylogénétiques et morphologiques complémentaires.
Asunto(s)
Aedes , Ochlerotatus , Aedes/anatomía & histología , Animales , Secuencia de Bases , Masculino , Ochlerotatus/genética , Filogenia , PupaRESUMEN
Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The country also shares common borders with northern Mauritania, where RVF is often documented. Human movement, livestock trade, climate changes and the availability of susceptible mosquito vectors are expected to increase the spread of these diseases in the country. Thus, in this study, we gathered a data set summarizing occurrences of Ae. caspius, Ae. detritus and Cx. pipiens in the country, and generated model prediction for their potential distribution under both current and future (2050) climate conditions, as a proxy to identify regions at-risk of RVF and WNV probable expansion. We found that the north-western regions (where the population is most concentrated), specifically along the Atlantic coastline, are highly suitable for Ae. caspius, Ae. detritus and Cx. pipiens, under present-day conditions. Future model scenarios anticipated possible range changes for the three mosquitoes under all climatic assumptions. All of the studied species are prospected to gain new areas that are currently not suitable, even under the most optimist scenario, thus placing additional human populations at risk. Our maps and predictions offer an opportunity to strategically target surveillance and control programmes. Public health officials, entomological surveillance and control delegation must augment efforts and continuously monitor these areas to reduce and minimize human infection risk.
Asunto(s)
Aedes , Culex , Enfermedades de los Caballos , Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Fiebre del Nilo Occidental , Virus del Nilo Occidental , Animales , Caballos , Humanos , Insectos Vectores , Marruecos/epidemiología , Fiebre del Valle del Rift/epidemiología , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/veterinariaRESUMEN
Aedes caspius has a wide distribution throughout the world and can transmit Chikungunya virus, West Nile Virus (WNV), Tahyna virus and the bacterium Francisella tularensis. Sequences of the mitochondrial cytochrome C-oxidase subunit 1 (COI) and cytochrome C-oxidase subunit 2 (COII) genes have been widely used to estimate phylogenetic relationships at different taxonomic levels among this species. Adult collections were carried out by human bait, Center for Deseases Control Light Traps (CDC-LT) and aspirator during February/April, June and October/December 2013-2015 from different southern provinces of Iran and then identified morphologically with reliable keys. A total of 3,570 adult mosquitoes were collected and identified as belonging to three genera, including five species of Culex, six species of Aedes and one species of Culiseta. In this study, 1,796 specimens of Aedes caspius were identified from four provinces. Based on the COI and COII sequences obtained for Ae. caspius population, 12 and 11 haplotypes were identified, respectively. The present study evidenced a high degree of intraspecific variation among these populations of Ae. caspius.
Aedes caspius largement distribué dans le monde est le vecteur du virus du chikungunya, du virus West Nile, du virus Tahyna et de la bactérie Francisella tularensis. Les séquences des gènes mitochondriaux COI et COII sont généralement utilisées pour estimer les relations phylogénétiques entre les différents niveaux taxonomiques de cette espèce. Des moustiques adultes ont été collectés sur appâts humains, à l'aide de pièges lumineux de type « CDC/light-trap ¼ et d'aspirateurs en février/avril, juin et octobre/décembre 20132015 dans les provinces au sud de l'Iran. Les moustiques ont ensuite été identifiés d'un point de vue morphologique. Trois mille cinq cent soixante-dix moustiques adultes ont été collectés et identifiés comme appartenant à trois genres, dont cinq espèces de Culex, six espèces d'Aedes et une espèce de Culiseta. Dans cette étude, 1 796 spécimens d'Aedes caspius ont été identifiés dans quatre provinces. Les séquences COI et COII des populations d'Ae. caspius ont permis d'identifier respectivement 12 et 11 haplotypes. Les résultats de cette étude ont démontré qu'il existe une forte variation intraspécifique dans ces populations d'Ae. caspius.
Asunto(s)
Aedes/clasificación , Aedes/genética , Variación Genética , Aedes/virología , Animales , Culex/clasificación , Culex/genética , Culex/virología , Culicidae/clasificación , Culicidae/genética , Código de Barras del ADN Taxonómico , Complejo IV de Transporte de Electrones/genética , Genética de Población , Irán , Mosquitos Vectores/clasificación , Mosquitos Vectores/genética , Filogenia , Estaciones del Año , Análisis de Secuencia de ADNRESUMEN
Beside numerous extensive studies on Anophelinae mosquitoes of Iran, little is known on Aedes species in the country and existing reports are dispersed. The objective of this study was to identify adults of Culicinae species occurring in the Sistan and Baluchestan Province, southeast of Iran, during 2012-2014. Mosquito collections were carried out three times (May-June, September, October-November) in four counties by Centers for Diseases Control (CDC) light traps and human landing catches outdoors and under bed nets baited with carbon dioxide. These trapping were carried out two consecutive nights during the field studies. Several mosquito collections were also conducted with aspirator and pyrethrum spray space catches during the day. A total of 1885 mosquitoes were collected, belonging to 10 species of genus Culex including Cx. pipiens Complex, Cx. laticinctus, Cx. sinaiticus, and Cx. tritaeniorhynchus, one species of the genus Culiseta, Cs. longiareolata, and five species of the genus Aedes, Ae. caspius, Ae. vexans, Ae. detritus, Ae. albopictus, and Ae. unilineatus. Ae. vexans was the dominant species in the area (77.7%). During the study, seven Ae. unilineatus were collected in two villages near the city of Chabahar located in a coastal area; this is the first record for Iran and identification was confirmed by Cytochrome oxidase (COI) sequences analysis. Confirmation of the presence of Ae. unilineatus in the country raises the number of species of the genus Aedes to 12. The detection of this species reveals its probable establishment in the southeast of the country, which has implications for public health such as dengue and Zika infections and requires active entomological surveillance and implementation of adapted vector control measures in the area.