Journal of Medical Entomology最新文献

Simulium (Asiosimulium) khongchiamense sp. nov. is described based on females, males, pupae, and mature larvae collected from Khong Chiam District, Ubon Ratchathani Province, northeastern Thailand. It is characterized in the female by the medium-long sensory vesicle, scutum with 3 dark longitudinal vittae and elongate cercus; in the male by the number of upper-eye (large) facets in 17 or 18 vertical rows and 18 or 19 horizontal rows, hind basitarsus moderately enlarged and ventral plate with the posterior margin moderately concave medially; in the pupa by the head and thoracic integument sparsely covered with tubercles and gill of arborescent type with 32 or 33 filaments; and in the larva by the postgenal cleft deep, reaching the posterior margin of the hypostoma and sheath of the subesophageal ganglion dark pigmented. DNA analysis based on COI gene of all known species of the subgenus Asiosimulium, except for S. shanense and S. suchitrae, indicated that this new species can be clearly differentiated from all other related species (S. phurueaense, S. oblongum, S. saeungae, S. furvum, and S. wanchaii) with interspecific genetic distances ranging between 4.79% and 19.18%. This is the eighth species of the subgenus Asiosimulium. Taxonomic notes are given to distinguish this new species from the 7 known species members in its same subgenus. Additionally, keys to species of all members in the subgenus Asiosimulium are provided.

Transgenesis has emerged as a powerful tool to control arthropod vectors and the diseases they transmit. Here, we highlight the latest developments on transgenic approaches in ticks, Anopheles and Aedes mosquitoes, based on recent findings and significant papers from 2022. We survey topics ranging from population replacement, population suppression, gene drive, sex ratio distortion, public engagement and capacity building, and gene editing in ticks. While presenting these advancements, we discuss the current challenges surrounding the application of arthropod transgenesis for the development of novel vector control strategies.

Aedes koreicus (Edward, 1917) (Diptera: Culicidae), a mosquito species native to East Asia, has spread to parts of Europe and Central Asia since 2008. The species shares ecological characteristics with Aedes japonicus (Theobald, 1901) (Diptera: Culicidae), which has already successfully invaded and established in North America and Europe. Given these similarities, it is plausible that Ae. koreicus may also invade North America in the future. However, the invasion of Ae. koreicus may be masked or have delayed detection due to their similar morphologies with Ae. japonicus. This study highlights the potential risks of invasion of Ae. koreicus into North America, especially in the northeastern United States, and for further expansion in Europe. We used the maximum entropy model to identify areas with a high likelihood of presence in North America and Europe using comprehensive occurrence records from East Asia, Central Asia, and Europe. We have identified 15 additional countries in Europe and 7 states in the United States that will likely have suitable environments for Ae. koreicus. Additionally, we reviewed the morphological characteristics of Ae. koreicus and Ae. japonicus and provided morphological keys to distinguish the 2 species. Morphological results contradicting previous studies suggested that finding the origin by morphological comparison between Ae. koreicus populations may need re-evaluation. The information presented here will be useful for researchers and public health professionals in high-risk areas to be informed about morphological characteristics to distinguish Ae. koreicus from similar-looking Ae. japonicus. These tools will allow more careful monitoring of the potential introduction of this highly invasive species.

This article deals with the morphological and molecular assessments of 3 species of mosquitoes collected in Yunnan Province, China, i.e Anopheles monticola Somboon, Namgay & Harbach, the only species of the Baileyi Complex identified, Culex sasai Kano, Nitahara & Awaya, and Lutzia vorax Edwards. Interestingly, some adult specimens of An. monticola exhibited a variant form in having pale fringe spots, as found in An. simlensis James, another species of the Baileyi Complex. Culex sasai was recorded for the first time in Yunnan and mainland China. The prevalence of Lt. vorax was confirmed, and previous records of Lt. halifaxii in China are regarded as misidentifications of Lt. vorax.

House fly (Musca domestica L.) (Diptera: Muscidae) populations can negatively impact poultry layer facilities, posing a risk to human and animal health and egg food safety. House flies quickly develop resistance to traditional chemical control methods; therefore, improved biological control may provide opportunities for improved integrated pest management (IPM) programs. Biological control methods currently used include augmentative releases of pteromalid pupal parasitoids and application of the fungal entomopathogen Beauveria bassiana (Balsamo) Vuillemin. This study used bioassays to compare the impact of different B. bassiana strains on survival of house flies and of 3 species of filth fly parasitoids. The B. bassiana that were compared were 3 new field-collected isolates, an older field-collected isolate (L90), and a common commercially available strain (GHA). Flies and parasitoids were exposed to filter paper treated with 1.5 × 109 spores of each strain and a control. All field-isolated strains induced lower mean survival times in house flies than GHA did. The results for all species of parasitoids demonstrated less difference among the treatment groups and the control than in-house flies. Although there was some effect of B. bassiana exposure on parasitoid mortality, the expected spatial separation of parasitoids from areas of application may offer some protection. Using the most effective tested strains of B. bassiana and filth fly parasitoids jointly could be a biological component of an IPM plan for fly control in poultry facilities.

Globalization, increased frequency of travel, and a rise in legal and illegal animal trades can introduce exotic ticks into the United States. We herein report the importation of a male Rhipicephalus pulchellus (Gerstäcker) on a human traveler returning to Connecticut from Tanzania, Africa, and review historical importation records of this species into the United States. This common tick is broadly distributed throughout East Africa, from Eritrea to Tanzania, has a wide host range on domestic animals and wildlife, and has been most frequently introduced into the United States on tick-infested wild animal hosts and animal trophies, but documentation of importation on humans has been rare. Archival records at the United States Department of Agriculture's National Veterinary Services Laboratories show R. pulchellus has been introduced into the United States at least 40 times over the last 62 yr. Rhipicephalus pulchellus has been linked to Rickettsia conorii, the agent of boutonneuse fever in humans, Crimean-Congo hemorrhagic fever orthonairovirus, and Nairobi sheep disease orthonairovirus. Given the potential for this exotic tick to introduce animal or human pathogens, proper surveillance, interception, identification, and reporting of these ticks are vital in protecting human and animal health.

The first established population of the Asian longhorned tick Haemaphysalis longicornis (Neumann, Acari: Ixodidae) was discovered in a northern South Carolina county in June 2022. A coordinated investigation was launched to investigate the invasive tick's pathogen infection prevalence and blood meal preferences. Almost 2,000 Ha. longicornis ticks were collected from one cattle field. A majority of collected ticks had evidence of cattle and dog blood meals, and multiple samples were tested positive for Borrelia burgdorferi s.l. and Theileria orientalis-first reports for these pathogens in this tick species in South Carolina. This investigation was the direct result of a collaborative education campaign and tick surveillance program launched earlier in the year with multiple state partners.

Zoos provide a unique opportunity to study mosquito feeding ecology as they represent areas where exotic animals, free-roaming native animals, humans, and mosquito habitats overlap. Therefore, these locations are a concern for arbovirus transmission to both valuable zoo animals and human visitors. We sampled mosquitoes in and around The Nashville Zoo at Grassmere in Tennessee, USA, over 4 months in 2020 using 4 mosquito trap methods and 12 sampling locations. Mosquitoes were identified to species, Culex mosquitoes were analyzed for arboviruses, and all engorged mosquitoes were preserved for host usage analysis. We captured over 9,000 mosquitoes representing 27 different species, including a new species record for Davidson County, TN (Culex nigripalpus Theobald). Minimum infection rates for West Nile virus (WNV) (Flaviviridae: Flavivirus), St. Louis encephalitis virus (Flaviviridae: Flavivirus), and Flanders virus (Hapavirus: Rhabdoviridae) were 0.79, 0, and 4.17, respectively. The collection of 100 engorged mosquitoes was dominated by Culex pipiens pipiens Linnaeus (38%), Culex erraticus Dyar and Knab (23%), and Culex pipiens pipiens-Culex pipiens quinquefasciatus hybrids (10%). Host DNA from 84 engorged mosquitoes was successfully matched to a variety of host species (n = 23), with just 8 species belonging to the zoo. Wild birds were the most frequently fed upon host, in particular northern cardinals (Cardinalis cardinalis L. Passeriformes: Cardinalidae), which are competent WNV reservoirs. Taken together, our results demonstrate the utility of zoos as sentinels for emerging pathogens, for studying wildlife and human risk of zoonotic diseases, and for assessing vector diversity.

Uranotaenia bhutanensis Somboon, Namgay & Harbach was recently described as a new species of the Bimaculata Series of the subgenus Pseudoficalbia Theobald based on larvae collected from a log hole at high altitude in Bhutan. The adult female and pupa are described in this article based on the subsequent discovery of 2 paratype females with associated pupal exuviae.

Phlebotomus perniciosus is the most important vector of Leishmania infantum in the Western part of the Mediterranean basin. Atypical specimens of Ph. perniciosus called (pna) with a parameral sheath simply curved, not bifurcated, have been reported in many locations. In this study, we describe abnormal Ph. perniciosus male specimens. Sand flies were collected in center Tunisia and identified morphologically. Cytochrome b PCR-sequencing was carried out for abnormal Ph. perniciosus male specimens in order to confirm the morphological identification and assess the intraspecific genetic polymorphism. Abnormal Ph. perniciosus specimens were characterized by a multifurcated parameral sheath. A parsimonious haplotype network based on cyt b locus analysis showed that typical and abnormal Ph. perniciosus described in our investigation were grouped together in the same branch. Thus, genetic outcomes confirmed that the new phenotype is only an original morphotype of Ph. perniciosus.