RESUMO
Panstrongylus geniculatus is the most widely distributed species of Panstrongylus in Brazil and merits attention from vector control programs due to its potential for domiciliation. Specimens infected with Trypanosoma cruzi have already been reported in both peridomiciliary and domiciliary environments. Building on these findings, we report, for the first time, the presence of P. geniculatus in the state of Alagoas and provide an updated dichotomous key (based on cytogenetic data) for species in Alagoas. Panstrongylus geniculatus has been identified in Boca da Mata, Joaquim Gomes, and Novo Lino. In light of the recent notification of Rhodnius domesticus and this record of P. geniculatus, we present an updated identification key enabling the differentiation of all species in Alagoas. Emphasis is placed on the importance of correctly identifying triatomine species because it is crucial for the development of effective control measures, thereby aiding in the mitigation of Chagas disease.
RESUMO
Triatomines of the species Triatoma sherlocki are considered sylvatic; however, household invasion appears imminent, potentially carrying Trypanosoma cruzi, the causative agent of Chagas disease. The aim of this study was to report the first occurrence of a colony of T. sherlocki infected by T. cruzi in a subsistence pig farm. Triatomines collected underwent polymerase chain reaction (PCR) technique for T. cruzi detection and determination of blood meal source. The 19 triatomines collected in the pig farm were of the species T. sherlocki, comprising 26.3% nymphs (5/19), 52.6% males (10/19) and 21.1% females (4/19). PCR showed that 15.8% (3/19) of triatomines were infected by T. cruzi. The only detected blood meal source in triatomines (n = 11) was the domestic mammal Sus scrofa, commonly known as domestic pig, indicating that T. sherlocki is an opportunist, feeding on available vertebrates in the environment, including domestic animals such as pigs. These results highlight the possibility of domiciliation of the species T. sherlocki and its potential role in bridging the transmission of T. cruzi between sylvatic and domestic environments.
RESUMO
BACKGROUND: Rhodnius zeledoni was described from a single specimen. Since its description, doubts have arisen regarding the taxonomic status of this species in relation to Rhodnius domesticus. METHODS: The present study reviewed and compared R. zeledoni with R. domesticus based on morphological analysis and head geometric morphometrics. RESULTS: Our analysis revealed the absence of distinctive diagnostic characters between the two species at specific levels. Rhodnius zeledoni and R. domesticus show morphological and morphometric similarity, with only minor differences in coloration observed between them. Contrary to previous statements, our analysis showed that R. zeledoni and R. paraensis are not closely related species, not corroborating previous studies with such an assumption. CONCLUSIONS: Therefore, we formally propose R. zeledoni as a junior synonym of R. domesticus.
RESUMO
Chagas disease (CD) is a typical tropical illness caused by Trypanosoma cruzi. The objective of this study was to assess the prevalence of Chagas disease in communities in two states of the Brazilian Amazon. Data collection occurred in July in the Alto Juruá region of Acre and in December in the communities of Humaitá, Amazonas, in 2019. A total of 477 participants were included in the study. In the communities of Alto Juruá, triatomine collections and analyses of T. cruzi infection were also carried out. All confirmed cases were found in the state of Acre, resulting in a total prevalence of 1.67. Of these eight cases, seven underwent ECG, all of which were concluded as normal by the physician team's cardiologists. Seventeen triatomine bugs, all belonging to the Rhodnius genus, were captured. The natural infection rate by T. cruzi was 25% in the Nova Cintra community and 66.67% in the Boca do Moa community (Alto Juruá). This research found that more than 1% of the studied population exhibited positive serological results for Chagas disease in the riverine communities during the study period, representing a small portion of cases among those who have not yet been diagnosed.
RESUMO
Morphological studies applied to the taxonomy of the Triatominae cover various structures (head, wing, thorax, genitalia, and eggs). Exochorial structures of hybrid eggs were characterized and compared with the parents, demonstrating that hybrids presented characteristics identical to the exochorial pattern observed in the females of the crosses, which resulted in the hypothesis that the pattern of triatomine eggs is possibly a characteristic inherited from females. Thus, we characterized the exochorium of the eggs of several triatomine hybrids and compared them with the parents, to assess the pattern of segregation and test the hypothesis of maternal inheritance. Hybrids were obtained in at least one direction from all crosses. The analysis of the exochorium of the eggs of the hybrids showed different patterns of segregation: "exclusively paternal", "predominantly maternal", "predominantly paternal", "mutual", and "differential". Curiously, none of the hybrids evaluated presented characteristics that segregated exclusively from the female parental species. Thus, we demonstrate that the hypothesis of maternal inheritance of the exochorium pattern of eggs is not valid and we emphasize the importance of alternative/combined tools (such as integrative taxonomy) for the correct identification of these insect vectors (mainly in view of possible natural hybridization events due to climate and environmental changes).
Assuntos
Doença de Chagas , Triatominae , Animais , Feminino , Herança Materna , Doença de Chagas/genética , Triatominae/genética , Clima , Insetos Vetores/genéticaRESUMO
Triatomines are hematophagous insects of epidemiological importance as they are vectors of Chagas disease. The first report of Rhodnius stali Lent, Jurberg & Galvão, 1993 in Rondônia, Brazil, is described. The insects were captured on palm trees of the genus Oenocarpus sp. Two adult male specimens of R. stali were identified and were found to be infected with Trypanosoma cruzi and Trypanosoma rangeli. The confirmation of this Rhodnius species in Rondônia increases the number of triatomines from nine to ten species in this state.
RESUMO
Kodormusdavidmartinsisp. nov. is described. Taxonomic notes on the other species of Kodormus Barber, 1930, including the description of their male genitalia, are provided. The record of Kodormusbruneosus Barber, 1930 from Brazil and information about the female of the species are presented for the first time. A redescription of Kodormus and a key for its species are provided. Photographs of the holotypes of K.barberi (Costa Lima, 1941), K.bruneosus, and of a paratype of K.oscurus Maldonado & Bérenger, 1996 are presented.
RESUMO
Triatominae are associated with various Brazilian habitats, including bird nests, animal burrows, and peridomestic structures. Despite extensive studies on triatomines in domiciliary environments in Ceará, Brazil, there has been limited research on their presence in the wild. This study focuses on the municipality of Morrinhos in Ceará, which is characterized by a Caatinga biome and riparian forests along the Acaraú River. During the study, a total of 185 nests of Pseudoseisura cristata were analyzed in rural locations and triatomines were collected in 26 nests from 12 different locations. A total of 117 triatomines was collected, belonging to three species: Psammolestes tertius, Rhodnius nasutus, and Triatoma pseudomaculata. Rhodnius nasutus was the only species found in a nest inhabited by Didelphis albiventris. Nests of P. cristata serve as shelters for various animals, providing an ideal environment for triatomines to establish colonies due to their proximity to food sources and their generalist feeding habits. The incorporation of anthropogenic materials by birds in nest construction can indirectly affect the presence of other animals that may serve as food sources for triatomines. Understanding the interactions between triatomines, birds, and their habitats is essential for assessing the risks associated with triatomine infestation in wild ecosystems.
Assuntos
Doença de Chagas , Rhodnius , Triatoma , Triatominae , Trypanosoma cruzi , Animais , Brasil , Ecossistema , Insetos Vetores , AvesRESUMO
BACKGROUND: Hybridization events between Triatoma spp. have been observed under both natural and laboratory conditions. The ability to produce hybrids can influence different aspects of the parent species, and may even result in events of introgression, speciation and extinction. Hybrid sterility is caused by unviable gametes (due to errors in chromosomal pairing [meiosis]) or by gonadal dysgenesis (GD). All of the triatomine hybrids analyzed so far have not presented GD. We describe here for the first time GD events in triatomine hybrids and highlight these taxonomic and evolutionary implications of these events. METHODS: Reciprocal experimental crosses were performed between Triatoma longipennis and Triatoma mopan. Intercrosses were also performed between the hybrids, and backcrosses were performed between the hybrids and the parent species. In addition, morphological and cytological analyzes were performed on the atrophied gonads of the hybrids. RESULTS: Hybrids were obtained only for the crosses T. mopanâ × T. longipennisâ. Intercrosses and backcrosses did not result in offspring. Morphological analyses of the male gonads of the hybrids confirmed that the phenomenon that resulted in sterility of the hybrid was bilateral GD (the gonads of the hybrids were completely atrophied). Cytological analyses of the testes of the hybrids also confirmed GD, with no germ cells observed (only somatic cells, which make up the peritoneal sheath). CONCLUSIONS: The observations made during this study allowed us to characterize, for the first time, GD in triatomines and demonstrated that gametogenesis does not occur in atrophied gonads. The characterization of GD in male hybrids resulting from the crossing of T. mopanâ × T. longipennisâ highlights the importance of evaluating both the morphology and the cytology of the gonads to confirm which event resulted in the sterility of the hybrid: GD (which results in no gamete production) or meiotic errors (which results in non-viable gametes).
Assuntos
Doença de Chagas , Disgenesia Gonadal , Infertilidade , Triatoma , Triatominae , Masculino , Animais , Triatominae/genética , Fluxo Gênico , Triatoma/genética , Gônadas , Hibridização Genética , Vetores de DoençasRESUMO
BACKGROUND: Triatominae are vectors of the protozoan Trypanosoma cruzi, the causative agent of Chagas disease. This study aims to report an infestation on Triatominae colonies by a beetle, previously identified as a pest. METHODS: The management of these colonies should be improved to maximize their usefulness, and factors that may cause harm to them should be avoided as much as possible. RESULTS: This is the first report on a coleopteran infestation on living Triatominae colonies worldwide. CONCLUSIONS: The present record provides an important warning to researchers who maintain insectaries in general, especially those who rear triatomines, to carry protective measures against such invasions.
Assuntos
Doença de Chagas , Besouros , Reduviidae , Triatominae , Trypanosoma cruzi , Animais , Insetos VetoresRESUMO
Rhodnius amazonicus has been previously reported in the Brazilian states of Amazonas and Pará, as well as in French Guiana. However, this is the first recorded presence of this species in Amapá, which is situated in the northern region of Brazil. The specimen was collected from a house in the rural area of the municipality of Porto Grande. Other triatomines, such as Panstrongylus geniculatus, Rhodnius pictipes, and Eratyrus mucronatus, were also found in the same locality in different houses. These species are vectors of Trypanosoma cruzi, which causes Chagas disease. Therefore, this report may contribute to understanding transmission in the state of Amapá, where new infections and outbreaks of Chagas disease have been recorded.
RESUMO
Quasigraptocleptesmaracristinaegen. nov., sp. nov. (Hemiptera, Heteroptera, Reduviidae, Harpactorinae, Harpactorini) is described based on male and female specimens from Brazil. Photographs and comments about the syntypes of Myocorisnigriceps Burmeister, 1835, Myocorisnugax Stål, 1872, Myocoristipuliformis Burmeister, 1838 and Xystonyttusichneumoneus (Fabricius, 1803) are presented. The intra-specific variability and sexual dimorphic characteristics among specimens of Q.maracristinaesp. nov. are recorded. General characteristics of Hiranetis Spinola, 1837, Graptocleptes Stål, 1866, Quasigraptocleptesgen. nov. and Parahiranetis Gil-Santana, 2015, which seem to be closer genera, are compared, including those of the male genitalia of some species. A key to the species of Myocoris Burmeister, 1835, and an updated key to Neotropical wasp-mimicking Harpactorini genera are provided.
RESUMO
Chagas disease (CD) is a neglected illness affecting approximately seven million individuals, with vector transmission occurring via triatomine bugs. The Rhodniini tribe comprises 24 species, grouped into the Rhodnius and Psammolestes genera. Given the importance of accurately identifying CD vectors, the taxonomy of Psammolestes spp. was revisited using morphological and morphometric data. Specimens of P. tertius, P. coreodes, and P. arthuri were collected, and the morphological characteristics of the head, thorax, abdomen, and eggs were analyzed. Morphometric studies of eggs were also conducted. Dichotomous keys allowing for the differentiation of Psammolestes spp. were elaborated based on adult insect and egg morphological characteristics. Through these studies, it was possible to differentiate the three Psammolestes species and confirm that this genus should not be classified under the Rhodnius genus, contributing to Rhodniini taxonomy.
RESUMO
BACKGROUND: Triatomines infest atypical public spaces in the Western Amazon. METHODS: Frequent visitors to these spaces captured the insects in the state of Acre, Brazil (Rio Branco and Cruzeiro do Sul). RESULTS: Six insects were found in a penitentiary, a church, a school, a university, a hospital, and a health center. Five of the insects were adults (three positive for Trypanosoma cruzi) and one was a nymph. CONCLUSIONS: This is the first report of triatomine occurrence in schools or churches. These data are important for implementing surveillance strategies and alerting individuals about possible changes in Chagas disease transmission dynamics.
Assuntos
Doença de Chagas , Rhodnius , Trypanosoma cruzi , Animais , Adulto , Humanos , Brasil/epidemiologia , Insetos VetoresRESUMO
Several cytogenetic studies have already been performed in Triatominae, such that different karyotypes could be characterized (ranging from 2n = 21 to 25 chromosomes), being the changes in the number of chromosomes related mainly to fusion and fission events. These changes have been associated with reproductive isolation and speciation events in other insect groups. Thus, we evaluated whether different karyotypes could act in the reproductive isolation of triatomines and we analyzed how the events of karyotypic evolution occurred along the diversification of these vectors. For this, experimental crosses were carried out between triatomine species with different karyotypes. Furthermore, based on a phylogeny with 88 triatomine taxa (developed with different molecular markers), a reconstruction of ancestral karyotypes and of anagenetic and cladogenetic events related to karyotypic alterations was performed through the ChromoSSE chromosomal evolution model. All crosses performed did not result in hybrids (prezygotic isolation in both directions). Our modeling results suggest that during Triatominae diversification, at least nine cladogenetic events may be associated with karyotype change. Thus, we emphasize that these alterations in the number of chromosomes can act as a prezygotic barrier in Triatominae (karyotypic isolation), being important evolutionary events during the diversification of the species of Chagas disease vectors.
Assuntos
Doença de Chagas , Reduviidae , Triatominae , Animais , Triatominae/genética , Reduviidae/genética , Doença de Chagas/genética , Cariótipo , Filogenia , Aberrações Cromossômicas , Vetores de DoençasRESUMO
Chagas disease affects about eight million people. In view of the issues related to the influence of anthropogenic changes in the dynamics of the distribution and reproductive interaction of triatomines, we performed experimental crosses between species of the Rhodniini tribe in order to evaluate interspecific reproductive interactions and hybrid production capacity. Reciprocal crossing experiments were conducted among Rhodnius brethesi × R. pictipes, R. colombiensis × R. ecuadoriensis, R. neivai × R. prolixus, R. robustus × R. prolixus, R. montenegrensis × R. marabaensis; R. montenegrensis × R. robustus, R. prolixus × R. nasutus and R. neglectus × R. milesi. With the exception of crosses between R. pictipes â × R. brethesi â, R. ecuadoriensis â × R. colombiensis â and R. prolixus â × R. neivai â, all experimental crosses resulted in hybrids. Our results demonstrate that both allopatric and sympatric species produce hybrids, which can generate concern for public health agencies in the face of current anthropogenic events. Thus, we demonstrate that species of the Rhodniini tribe are capable of producing hybrids under laboratory conditions. These results are of great epidemiological importance and raise an important discussion about the influence of climatic and environmental interactions on Chagas disease dynamics.
RESUMO
Triatoma rubrovaria subcomplex consists of T. carcavalloi, T. circummaculata, T. klugi, T. limai, T. oliveirai, T. pintodiasi, T. rubrovaria, T. patagonica and T. guasayana, which can be vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease. In this study, morphological, morphometric, and genetic characters of T. circummaculata, T. pintodiasi, T. carcavalloi, T. klugi, and T. rubrovaria were analyzed in view of the integrative taxonomy and phylogeny of the T. rubrovaria subcomplex. Molecular studies were carried out through the sequencing and analysis of the mitochondrial genes COI and CytB, nuclear genes ITS I, ITS 2, 16S, and 28S from rDNA and rescued a monophyletic group. Furthermore, differential morphological characters were found among the five species in the pronotum, scutellum, stridulatory sulcus, male genitalia, and external female genitalia. Finally, morphometric analyses made it possible to differentiate the five species. Phylogenetic analyzes rescued the relationship of T. pintodiasi with members of the T. rubrovaria subcomplex and demonstrated that this subcomplex is a monophyletic group composed of the species T. carcavalloi, T. circummaculata, T. klugi, T. guasayana, T. limai, T. oliveirai, T. patagonica, T. pintodiasi, and T. rubrovaria. Furthermore, through integrative taxonomy, it was possible to confirm the specific status of the species T. carcavalloi, T. circummaculata, T. pintodiasi, T. klugi, and T. rubrovaria, offering new useful morphological characters for the differentiation and characterization of these potential vectors and distributed in Southern Brazil.
Assuntos
Doença de Chagas , Triatoma , Triatominae , Animais , Masculino , Feminino , Triatoma/genética , Triatoma/anatomia & histologia , Filogenia , BrasilRESUMO
ABSTRACT Background: Triatomines infest atypical public spaces in the Western Amazon. Methods: Frequent visitors to these spaces captured the insects in the state of Acre, Brazil (Rio Branco and Cruzeiro do Sul). Results: Six insects were found in a penitentiary, a church, a school, a university, a hospital, and a health center. Five of the insects were adults (three positive for Trypanosoma cruzi) and one was a nymph. Conclusions: This is the first report of triatomine occurrence in schools or churches. These data are important for implementing surveillance strategies and alerting individuals about possible changes in Chagas disease transmission dynamics.
RESUMO
ABSTRACT Background: Triatominae are vectors of the protozoan Trypanosoma cruzi, the causative agent of Chagas disease. This study aims to report an infestation on Triatominae colonies by a beetle, previously identified as a pest. Methods: The management of these colonies should be improved to maximize their usefulness, and factors that may cause harm to them should be avoided as much as possible. Results: This is the first report on a coleopteran infestation on living Triatominae colonies worldwide. Conclusions: The present record provides an important warning to researchers who maintain insectaries in general, especially those who rear triatomines, to carry protective measures against such invasions.