ABSTRACT
Entomological research is vital for shaping strategies to control mosquito vectors. Its significance also reaches into environmental management, aiming to prevent inconveniences caused by non-vector mosquitoes like the Mansonia Blanchard, 1901 mosquito. In this study, we carried out a five-year (2019-2023) monitoring of these mosquitoes at ten sites in Porto Velho, Rondônia, using SkeeterVac SV3100 automatic traps positioned between the two hydroelectric complexes on the Madeira River. Throughout this period, we sampled 153,125 mosquitoes, of which the Mansonia genus accounted for 54% of the total, indicating its prevalence in the region. ARIMA analysis revealed seasonal patterns of Mansonia spp., highlighting periods of peak density. Notably, a significant decreasing trend in local abundance was observed from July 2021 (25th epidemiological week) until the end of the study. Wind speed was observed to be the most relevant meteorological factor influencing the abundance of Mansonia spp. especially in the Joana D'Arc settlement, although additional investigation is needed to comprehensively analyze other local events and gain a deeper understanding of the ecological patterns of this genus in the Amazon region.
Subject(s)
Culicidae , Seasons , Animals , Culicidae/physiology , Mosquito Vectors/physiology , Brazil , Meteorological ConceptsABSTRACT
Mansonia are aggressive mosquito species that are abundant in aquatic ecosystems where the macrophyte plants occur. These mosquitoes are commonly found across the Amazon/Solimões River basin. However, little is known about the oviposition behavior of these species. In the present study, we registered observations on the oviposition activity of 3 species: Mansonia amazonensis, Ma. humeralis, and Ma. cf. titillans, in 5 species of macrophytes in the vicinities of the Madeira River, Porto Velho, State of Rondônia, Brazil. Overall, 197 egg batches were collected. A greater amount of egg batches was found in Salvinia molesta as compared with other macrophytes sampled. In addition, 2 new oviposition habitats were noted in Ludwigia helmintorrhiza and Limnobium spongia. These findings will be important to understand the reproductive dynamics of these mosquitoes in the Brazilian Amazon basin.
Subject(s)
Culicidae , Ecosystem , Animals , Female , Brazil , Rivers , Oviposition , RainforestABSTRACT
The Oswaldoi-konderi Complex (Anopheles, Nyssorhynchus) is composed of five species that have been distinguished and delimited using DNA sequences of mitochondrial and nuclear genes. At least two species of the complex have been formally described, namely Anopheles oswaldoi s.s. and An. konderi; however, the identity of An. konderi s.s. is unclear because two morphologically similar species co-exist in the type-locality in the municipality of Coari, Amazonas state, Brazil. Moreover, the study of resurrection and designation of the neotype of An. konderi s.s. included a mixture of both forms. In the present study, mosquitoes were collected in Coari to establish the molecular identity of An. konderi s.s. and describe a new species based on morphological and molecular data. Six females were collected and separated individually for oviposition. The parental progenies were obtained from field collected females, fourth-instar larva, pupa, and female and male were employed for morphological characterization. Genomic DNA from one fourth-instar larva of each progeny was extracted and sequenced for the mtDNA COI barcode region, CAD gene, and the ITS2 rDNA nuclear region to establish the molecular identity of the two morphological forms of An. konderi s.l. The An. konderi neotype was re-examined. The morphological and molecular analyses revealed two distinct groups: the first group was identical to the neotype of An. konderi s.s., whereas the second was found to belong to the group informally referred to as An. sp. near konderi or An. konderi B, herein described as Anopheles tadei n. sp.
Subject(s)
Anopheles , Animals , Anopheles/genetics , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , Female , Larva/genetics , Male , PupaABSTRACT
BACKGROUND: Saliva of mosquitoes contains anti-platelet, anti-clotting, vasodilatory, anti-complement and anti-inflammatory substances that help the blood feeding process. The salivary polypeptides are at a fast pace of evolution possibly due to their relative lack of structural constraint and possibly also by positive selection on their genes leading to evasion of host immune pressure. RESULTS: In this study, we used deep mRNA sequence to uncover for the first time the sialomes of four Amazonian anophelines species (Anopheles braziliensis, A. marajorara, A. nuneztovari and A. triannulatus) and extend the knowledge of the A. darlingi sialome. Two libraries were generated from A. darlingi mosquitoes, sampled from two localities separated ~ 1100 km apart. A total of 60,016 sequences were submitted to GenBank, which will help discovery of novel pharmacologically active polypeptides and the design of specific immunological markers of mosquito exposure. Additionally, in these analyses we identified and characterized novel phasmaviruses and anpheviruses associated to the sialomes of A. triannulatus, A. marajorara and A. darlingi species. CONCLUSIONS: Besides their pharmacological properties, which may be exploited for the development of new drugs (e.g. anti-thrombotics), salivary proteins of blood feeding arthropods may be turned into tools to prevent and/or better control vector borne diseases; for example, through the development of vaccines or biomarkers to evaluate human exposure to vector bites. The sialotranscriptome study reported here provided novel data on four New World anopheline species and allowed to extend our knowledge on the salivary repertoire of A. darlingi. Additionally, we discovered novel viruses following analysis of the transcriptomes, a procedure that should become standard within future RNAseq studies.
Subject(s)
Anopheles/genetics , Peptides/genetics , Saliva/chemistry , Salivary Proteins and Peptides/genetics , Amino Acid Sequence/genetics , Animals , Anopheles/chemistry , Brazil , Humans , Insect Vectors/chemistry , Insect Vectors/genetics , Mosquito Vectors/genetics , N-Acetylneuraminic Acid/chemistry , Peptides/chemistry , RNA, Messenger/genetics , Salivary Proteins and Peptides/chemistry , Selection, Genetic/geneticsABSTRACT
We report the first record of Aedes albopictus (Diptera: Culicidae) in the state of Amapá, northern Brazil. Two female specimens were collected from a Shannon trap in the locality of Ilha de Santana, municipality of Santana, Amapá. The occurrence of the species was confirmed with the installation of ten ovitraps. Aedes albopictus is a species of epidemiological importance for the transmission of arboviruses. Amapá was one of two Brazilian states without any record of this species. (AU)
Relatamos o primeiro registro de Aedes albopictus (Diptera: Culicidae) no Estado do Amapá, no norte do Brasil. Dois espécimes foram coletados em uma armadilha de Shannon na localidade de "Ilha de Santana", município de Santana, no Amapá. O registro foi confirmado com a instalação de dez ovitrampas. Aedes albopictus é uma espécie com importância epidemiológica na transmissão de arboviroses. O Amapá era um de dois estados brasileiros sem registro dessa espécie.(AU)
Subject(s)
Animals , Arboviruses , Aedes/classification , Arbovirus Infections/epidemiology , Species Specificity , BrazilABSTRACT
Recent studies have shown that Anopheles oswaldoi sensu lato comprises a cryptic species complex in South America. Anopheles konderi, which was previously raised to synonymy with An. oswaldoi, has also been suggested to form a species complex. An. oswaldoi has been incriminated as a malaria vector in some areas of the Brazilian Amazon, Colombia, Peru and Venezuela, but was not recognized as a vector in the remaining regions in its geographic distribution. The role of An. konderi as a malaria vector is unknown or has been misattributed to An. oswaldoi. The focus of this study was molecular identification to infer the evolutionary relationships and preliminarily delimit the geographic distribution of the members of these complexes in the Brazilian Amazon region. The specimens were sampled from 18 localities belonging to five states in the Brazilian Amazon and sequenced for two molecular markers: the DNA barcode region (COI gene of mitochondrial DNA) and Internal Transcribed Spacer 2 (ITS2 ribosomal DNA). COI (83 sequences) and ITS2 (27 sequences) datasets generated 43 and 10 haplotypes, respectively. Haplotype networks and phylogenetic analyses generated with the barcode region (COI gene) recovered five groups corresponding to An. oswaldoi s.s., An. oswaldoi B, An. oswaldoi A, An. konderi and An. sp. nr. konderi; all pairwise genetic distances were greater than 3%. The group represented by An. oswaldoi A exhibited three strongly supported lineages. The molecular dating indicated that the diversification process in these complexes started approximately 2.8 Mya, in the Pliocene. These findings confirm five very closely related species and present new records for these species in the Brazilian Amazon region. The paraphyly observed for the An. oswaldoi complex suggests that An. oswaldoi and An. konderi complexes may comprise a unique species complex named Oswaldoi-Konderi. Anopheles oswaldoi B may be a potential malaria vector in the extreme north of the Brazilian Amazon, whereas evidence of sympatry for the remaining species in other parts of the Brazilian Amazon (Acre, Amazonas, Pará and Rondônia) precluded identification of probable vectors in those areas.
Subject(s)
Anopheles/classification , Anopheles/genetics , Evolution, Molecular , Animals , Brazil , DNA Barcoding, Taxonomic , DNA, Intergenic/genetics , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , PhylogenyABSTRACT
INTRODUCTION: The muscoid fly Dermatobia hominis causes cutaneous myiases in mammals. Females of this species use a vector to carry their eggs to the host. This note describes Anopheles konderi acting as phoretic vector for D. hominis. METHODS: A female A. konderi carrying D. hominis was collected using light traps in Oriximiná, Pará, Brazil. The A. konderi specimen was identified at morphological and molecular levels. RESULTS: Eight eggs of D. hominis were observed on the Anopheles konderi female. CONCLUSIONS: Anopheles konderi, only the third Anopheles species recorded as a phoretic vector, may be a potential vector of D. hominis.
Subject(s)
Anopheles/parasitology , Animals , Anopheles/classification , Brazil , Diptera/growth & development , Female , Ovum , SymbiosisABSTRACT
Abstract INTRODUCTION: The muscoid fly Dermatobia hominis causes cutaneous myiases in mammals. Females of this species use a vector to carry their eggs to the host. This note describes Anopheles konderi acting as phoretic vector for D. hominis. METHODS: A female A. konderi carrying D. hominis was collected using light traps in Oriximiná, Pará, Brazil. The A. konderi specimen was identified at morphological and molecular levels. RESULTS: Eight eggs of D. hominis were observed on the Anopheles konderi female. CONCLUSIONS: Anopheles konderi, only the third Anopheles species recorded as a phoretic vector, may be a potential vector of D. hominis.
Subject(s)
Animals , Female , Anopheles/parasitology , Ovum , Symbiosis , Brazil , Diptera/growth & development , Anopheles/classificationABSTRACT
BACKGROUND: Anopheles nuneztovari sensu lato comprises cryptic species in northern South America, and the Brazilian populations encompass distinct genetic lineages within the Brazilian Amazon region. This study investigated, based on two molecular markers, whether these lineages might actually deserve species status. METHODS: Specimens were collected in five localities of the Brazilian Amazon, including Manaus, Careiro Castanho and Autazes, in the State of Amazonas; Tucuruí, in the State of Pará; and Abacate da Pedreira, in the State of Amapá, and analysed for the COI gene (Barcode region) and 12 microsatellite loci. Phylogenetic analyses were performed using the maximum likelihood (ML) approach. Intra and inter samples genetic diversity were estimated using population genetics analyses, and the genetic groups were identified by means of the ML, Bayesian and factorial correspondence analyses and the Bayesian analysis of population structure. RESULTS: The Barcode region dataset (N = 103) generated 27 haplotypes. The haplotype network suggested three lineages. The ML tree retrieved five monophyletic groups. Group I clustered all specimens from Manaus and Careiro Castanho, the majority of Autazes and a few from Abacate da Pedreira. Group II clustered most of the specimens from Abacate da Pedreira and a few from Autazes and Tucuruí. Group III clustered only specimens from Tucuruí (lineage III), strongly supported (97 %). Groups IV and V clustered specimens of A. nuneztovari s.s. and A. dunhami, strongly (98 %) and weakly (70 %) supported, respectively. In the second phylogenetic analysis, the sequences from GenBank, identified as A. goeldii, clustered to groups I and II, but not to group III. Genetic distances (Kimura-2 parameters) among the groups ranged from 1.60 % (between I and II) to 2.32 % (between I and III). Microsatellite data revealed very high intra-population genetic variability. Genetic distances showed the highest and significant values (P = 0.005) between Tucuruí and all the other samples, and between Abacate da Pedreira and all the other samples. Genetic distances, Bayesian (Structure and BAPS) analyses and FCA suggested three distinct biological groups, supporting the barcode region results. CONCLUSIONS: The two markers revealed three genetic lineages for A. nuneztovari s.l. in the Brazilian Amazon region. Lineages I and II may represent genetically distinct groups or species within A. goeldii. Lineage III may represent a new species, distinct from the A. goeldii group, and may be the most ancestral in the Brazilian Amazon. They may have differences in Plasmodium susceptibility and should therefore be investigated further.