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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.

Entomological collections help scientists to rapidly identify invasive insects that affect agriculture, forestry, and human and animal health and to infer about global change biology. There are several collections with deposited Chagas disease vectors that are distributed throughout the world, but most of them present in Brazil. Faced with the need to disclose the biological material deposited in these collections, Brazilian articles were published compiling the information about the Triatomines Collections of the Oswaldo Cruz Institute, the Collection of Chagas Disease Vectors, the Entomologic collections of the Faculty of Public Health of the University of Sao Paulo, and the Entomological Collection of Instituto Butantan. The Museum of the Institute of Agricultural Zoology “Francisco Fernández Yépez” (MIZA) in Venezuela has more than four million arthropods deposited in its collection, being more than 4,500 holotypes. Based on the importance of disseminating to the world the richness of species deposited in biological collections, with emphasis on the entomological collections of vectors that can present important epidemiological information on the distribution of the vector-borne diseases, the present work compiles all the information related to triatomines deposited in MIZA. Through the analysis of the triatomines deposited in the MIZA was possible to highlight that there are over one thousand triatomines deposited in the entomological collection, distributed in 39 species grouped in four tribes: Bolboderini (two species), Cavernicolini (one species), Rhodniini (seven species) and Triatomini (29 species). In additional, eleven new occurrence points were described for Venezuelan states, namely, Miranda (Cavernicola pilosa and Eratyrus mucronatus), Amazonas (Rhodnius pictipes and E. mucronatus), Aragua (R. robustus), Federal District (E. mucronatus), Barinas (Panstrongylus geniculatus), Bolívar (P. rufotuberculatus), Carabobo (Triatoma nigromaculata), Falcón (T. nigromaculata) and Táchira (T. nigromaculata). The analysis of the entomological collection of MIZA allowed to group important information on the richness of biological material deposited for the subfamily Triatominae, as well as for the epidemiology of Chagas disease in the States of Venezuela, emphasizing the importance of the dissemination of information on biological collections to the scientific community in the form of manuscripts or official sites aiming the internationalization and valuation of collections and deposited material.

Made available in DSpace on 2022-04-29T08:35:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Background: Triatoma sordida is one of the main Chagas disease vectors in Brazil. In addition to Brazil, this species has already been reported in Bolivia, Argentina, Paraguay, and Uruguay. It is hypothesized that the insects currently identified as T. sordida are a species subcomplex formed by three cytotypes (T. sordida sensu stricto [s.s.], T. sordida La Paz, and T. sordida Argentina). With the recent description of T. rosai from the Argentinean specimens, it became necessary to assess the taxonomic status of T. sordida from La Paz, Bolivia, since it was suggested that it may represent a new species, which has taxonomic, evolutionary, and epidemiological implications. Based on the above, we carried out molecular and experimental crossover studies to assess the specific status of T. sordida La Paz. Methods: To evaluate the pre- and postzygotic barriers between T. sordida La Paz and T. sordida s.s., experimental crosses and intercrosses between F1 hybrids and between F2 hybrids were conducted. In addition, cytogenetic analyses of the F1 and F2 hybrids were applied with an emphasis on the degree of pairing between the homeologous chromosomes, and morphological analyses of the male gonads were performed to evaluate the presence of gonadal dysgenesis. Lastly, the genetic distance between T. sordida La Paz and T. sordida s.s. was calculated for the CYTB, ND1, and ITS1 genes. Results: Regardless of the gene used, T. sordida La Paz showed low genetic distance compared to T. sordida s.s. (below 2%). Experimental crosses resulted in offspring for both directions, demonstrating that there are no prezygotic barriers installed between these allopatric populations. Furthermore, postzygotic barriers were not observed either (since the F1 × F1 and F2 × F2 intercrosses resulted in viable offspring). Morphological and cytogenetic analyses of the male gonads of the F1 and F2 offspring demonstrated that the testes were not atrophied and did not show chromosome pairing errors. Conclusion: Based on the low genetic distance (which configures intraspecific variation), associated with the absence of prezygotic and postzygotic reproductive barriers, we confirm that T. sordida La Paz represents only a chromosomal polymorphism of T. sordida s.s. Graphical abstract: [Figure not available: see fulltext.] Laboratório de Biologia Celular Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo, 2265 Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Parasitologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1 Laboratório de Entomologia em Saúde Pública Departamento de Epidemiologia Faculdade de Saúde Pública Universidade de São Paulo, Av. Dr. Arnaldo 715 Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos Instituto Oswaldo Cruz (FIOCRUZ), Av. Brasil 4365, Pavilhão Rocha Lima, sala 505 Laboratório de Biologia Celular Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo, 2265 Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Parasitologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1

Made available in DSpace on 2022-04-29T08:36:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Triatoma petrocchiae is a species morphologically similar to T. b. brasiliensis (which resulted in a synonymization event); despite this similarity, genetic, morphological, and experimental crossbreed-ing studies confirmed the specific status of T. petrocchiae. Considering that both species have been reported living in sympatry and that, for a long time, most species of the T. brasiliensis complex were considered only chromatic variants of T. b. brasiliensis, we carried out experimental crosses between T. b. brasiliensis and T. petrocchiae (to confirm whether these species are reproductively isolated) and between T. lenti and T. petrocchiae (to assess whether T. petrocchiae also presents prezygotic isolation with the other species of the T. brasiliensis complex). Reciprocal experimental crosses were conducted, and weekly, the eggs were collected, counted, and separated in new containers to assess the hatch rate. Neither cross resulted in hybrids, demonstrating that there are pre-zygotic reproductive barriers installed between T. petrocchiae and the other species of the T. brasiliensis complex. On the basis of the results above, we demonstrated that T. petrocchiae is reproductively isolated from T. b. brasilien-sis and T. lenti. Furthermore, we suggest that T. petrocchiae is the species most derived from the T. brasiliensis complex. Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Entomologia em Saúde Pública Departamento de Epidemiologia Faculdade de Saúde Pública Universidade de São Paulo (USP), Av. Dr. Arnaldo 715 Laboratório de Parasitologia Departamento de Ciências Biológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Câmpus de Araraquara, Rod. Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Câmpus de São José do Rio Preto Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Cristóvão Colombo 2265 Instituto de Biologia Universidade Estadual de Campinas (UNICAMP), Rua Monteiro Lobato, 255 Centro de Ciências Aplicadas e Educação Laboratório de Ecologia Animal Departamento de Engenharia e Meio Ambiente Universidade Federal de Paraíba (UFPB), Av. Santa Elizabete, 160, Rio Tinto Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos Instituto Oswaldo Cruz (IOC/FIOCRUZ), Av. Brasil 4365, Pavilhão Rocha Lima, Sala 505 Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Parasitologia Departamento de Ciências Biológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Câmpus de Araraquara, Rod. Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Câmpus de São José do Rio Preto Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Cristóvão Colombo 2265 CAPES: 001

Made available in DSpace on 2021-06-25T10:52:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Although all triatomines are considered as potential vectors of the Chagas disease, the Triatoma, Panstrongylus, and Rhodnius genera are the most important from the epidemiological point of view. Based on cytogenetic analyzes carried out so far (C banding and FISH), the species of the genus Rhodnius show little interspecific chromosomal variation. Thus, we analyzed the distribution of AT- and CG-rich DNA in the chromatin and chromosomes of the genus Rhodnius and discuss the chromosome evolution of these vectors. Except for Rhodnius domesticus, Rhodnius nasutus, Rhodnius pictipes, Rhodnius colombiensis, and Rhodnius pallescens, all Rhodnius species have euchromatic autosomes with the absence of AT- and CG-rich blocks. Curiously, the same species that have heterochromatin blocks in the autosomes also have chromomycin A3 (CMA3+) blocks dispersed in the prophasic nucleus (demonstrating that the heterochromatin of these species is rich in CG). Thus, we characterize the AT- and CG-rich DNA pattern for the genus Rhodnius, and we suggest that the pattern of CG-rich heterochromatin in the autosomes of these vectors evolved independently in pallescens, pictipes, and prolixus groups. Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (IBB/UNESP) Departamento de Ciências Biológicas Laboratório de Parasitologia Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (FCFAR/UNESP) Departamento de Biologia Laboratório de Biologia Celular Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” (IBILCE/UNESP) Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (IBB/UNESP) Departamento de Ciências Biológicas Laboratório de Parasitologia Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (FCFAR/UNESP) Departamento de Biologia Laboratório de Biologia Celular Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” (IBILCE/UNESP)

Made available in DSpace on 2022-04-29T08:30:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Background: The tribe Rhodniini is a monophyletic group composed of 24 species grouped into two genera: Rhodnius and Psammolestes. The genus Psammolestes includes only three species, namely P. coreodes, P. tertius and P. arthuri. Natural hybridization events have been reported for the Rhodniini tribe (for genus Rhodnius specifically). Information obtained from hybridization studies can improve our understanding of the taxonomy and systematics of species. Here we report the results from experimental crosses performed between P. tertius and P. coreodes and from subsequent analyses of the reproductive and morphological aspects of the hybrids. Methods: Crossing experiments were conducted between P. tertius and P. coreodes to evaluate the pre- and post-zygotic barriers between species of the Rhodniini tribe. We also performed cytogenetic analyses of the F1 hybrids, with a focus on the degree of pairing between the homeologous chromosomes, and morphology studies of the male gonads to evaluate the presence of gonadal dysgenesis. Lastly, we analyzed the segregation of phenotypic characteristics. Results: Interspecific experimental crosses demonstrated intrageneric genomic compatibility since hybrids were produced in both directions. However, these hybrids showed a high mortality rate, suggesting a post-zygotic barrier resulting in hybrid unviability. The F1 hybrids that reached adulthood presented the dominant phenotypic segregation pattern for P. tertius in both directions. These insects were then intercrossed; the hybrids were used in the cross between P. tertius ♀ × P. coreodes ♂ died before oviposition, and the F1 hybrids of P. coreodes ♀ x P. tertius ♂ oviposited and their F2 hybrids hatched (however, all specimens died after hatching, still in first-generation nymph stage, pointing to a hybrid collapse event). Morphological analyses of male gonads from F1 hybrids showed that they did not have gonadal dysgenesis. Cytogenetic analyses of these triatomines showed that there were metaphases with 100% pairing between homeologous chromosomes and metaphases with pairing errors. Conclusion: The results of this study demonstrate that Psammolestes spp. have intrageneric genomic compatibility and that post-zygotic barriers, namely unviability of hybrid and hybrid collapse, resulted in the breakdown of the hybrids of P. tertius and P. coreodes, confirming the specific status of species based on the biological concept of species. Graphical abstract: [Figure not available: see fulltext.] Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin 250, Distrito de Rubião Júnior Laboratório de Entomologia em Saúde Pública Departamento de Epidemiologia Faculdade de Saúde Pública Universidade de São Paulo (USP), Av. Dr. Arnaldo 715 Laboratório de Parasitologia Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rod. Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Cristovão Colombo 2265 Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos Instituto Oswaldo Cruz (FIOCRUZ), Av. Brasil 4365, Pavilhão Rocha Lima, sala 505 Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin 250, Distrito de Rubião Júnior Laboratório de Parasitologia Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rod. Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Cristovão Colombo 2265

Triatoma sordida is among the main Brazilian species considered as Chagas disease vectors. The genetic studies are directed mainly to phylogenetic questions because this species possibly have suffered cryptic speciation. Furthermore, there are few studies that analyzed the structure and genetic variability of specimens from Brazil and that showed low genetic diversity and strong genetic structuring of the population samples. Therefore, because of great epidemiological importance of T. sordida and mainly the restriction of genetic characterization of this vector only for populations of Minas Gerais state, this article performs a genetic analysis of the T. sordida from seven different Brazilian states (representing different biomes), by means of cytogenetic markers. All analyzed specimens presents the same cytogenetic characteristics: early meiotic prophase with several heterochromatic bodies dispersed in the nucleus (CG-rich), being one of them formed by the associated sex chromosomes surrounded by some autosomal heterochromatic regions, meiotic metaphase with most autosomal pairs exhibiting a C-heterochromatic block in one chromosomal end (CG-rich), Y sex chromosome fully heterochromatin (AT-rich), and X chromosome may present a small C-block (CG-rich). These results are important because the chromosomal markers enable to confirm and expand the low genetic diversity for all Brazilian states occupied by T. sordida, suggesting that all Brazilian populations were originated from a small ancestral population and possibly dispersed to other biomes by founder effect. In addition, we suggest that T. sordida from Brazil are not suffering cryptic speciation and we confirm the classification of all Brazilian examples as T. sordida sensu stricto.

Made available in DSpace on 2022-04-29T08:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Background: Meccus' taxonomy has been quite complex since the first species of this genus was described by Burmeister in 1835 as Conorhinus phyllosoma. In 1859 the species was transferred to the genus Meccus and in 1930 to Triatoma. However, in the twentieth century, the Meccus genus was revalidated (alteration corroborated by molecular studies) and, in the twenty-first century, through a comprehensive study including more sophisticated phylogenetic reconstruction methods, Meccus was again synonymous with Triatoma. Events of natural hybridization with production of fertile offspring have already been reported among sympatric species of the T. phyllosoma subcomplex, and experimental crosses demonstrated reproductive viability among practically all species of the T. phyllosoma subcomplex that were considered as belonging to the genus Meccus, as well as between these species and species of Triatoma. Based on the above, we carried out experimental crosses between T. longipennis (considered M. longipennis in some literature) and T. mopan (always considered as belonging to Triatoma) to evaluate the reproductive compatibility between species of the T. phyllosoma complex. In addition, we have grouped our results with information from the literature regarding crosses between species that were grouped in the genus Meccus with Triatoma, in order to discuss the importance of experimental crosses to confirm the generic reorganization of species. Results: The crosses between T. mopan female and T. longipennis male resulted in viable offspring. The hatching of hybrids, even if only in one direction and/or at low frequency, demonstrates reproductive compatibility and homeology between the genomes of the parents. Conclusion: Considering that intergeneric crosses usually do not result in viable offspring in Triatominae, the reproductive compatibility observed between the T. phyllosoma subcomplex species considered in the Meccus genus with species of the Triatoma genus shows that there is “intergeneric” genomic compatibility, which corroborates the generic reorganization of Meccus in Triatoma. Graphic Abstract: [Figure not available: see fulltext.] Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências, Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Entomologia em Saúde Pública Departamento de Epidemiologia Faculdade de Saúde Pública Universidade de São Paulo, Av. Dr. Arnaldo 715 Laboratório de Parasitologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1 Laboratório de Biologia Celular Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos Instituto Oswaldo Cruz (FIOCRUZ), Av. Brasil 4365, Pavilhão Rocha Lima, sala 505 Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências, Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Laboratório de Parasitologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1 Laboratório de Biologia Celular Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265

Chagas disease is the most prevalent neglected tropical disease in the Americas and makes an important contribution to morbidity and mortality rates in countries where it is endemic since 30 to 40% of patients develop cardiac diseases, gastrointestinal disorders, or both. In this paper, a new species of the genus Triatoma is described based on specimens collected in the Department San Miguel, Province of Corrientes, Argentina. Triatoma rosai sp. nov. is closely related to T. sordida (St&aring, l, 1859), and was characterized based on integrative taxonomy using morphological, morphometric, molecular data, and experimental crosses. These analyses, combined with data from the literature (cytogenetics, electrophoresis pattern, molecular analyses, cuticular hydrocarbons pattern, geometric morphometry, cycle, and average time of life as well as geographic distribution) confirm the specific status of T. rosai sp. nov. Natural Trypanosoma cruzi infection, coupled with its presence mostly in peridomestic habitats, indicates that this species can be considered as an important Chagas disease vector from Argentina.

Made available in DSpace on 2021-06-25T11:13:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) There are currently 156 species, grouped into 18 genera and five tribes included in the subfamily Triatominae. All of them are potential vectors of Chagas disease. Triatoma is paraphyletic and the species of this genus have been grouped into complexes and subcomplexes. Triatoma brasiliensis complex is a monophyletic group composed of eight taxa: T. b. brasiliensis, T. b. macromelanosoma, T. juazeirensis, T. sherlocki, T. petrocchiae, T. lenti, T. bahiensis, T. melanica. Experimental crosses have helped in systematic, taxonomic and evolutionary issues of these vectors. Based on this, we carried out experimental crosses between T. lenti and four other species of the T. brasiliensis complex and analyzed the segregation pattern of phenotypic characteristics of T. lenti, T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis and T. melanica in the hybrids. The hybrids resulting from the crosses between T. b. brasiliensis ♀ x T. lenti ♂, T. juazeirensis ♀ x T. lenti ♂, and T. melanica ♀ x T. lenti ♂ showed segregation of characteristics of both parental species. On the other hand, the hybrids between T. lenti ♀ x T. juazeirensis ♂, T. b. macromelasoma ♀ x T. lenti ♂, and T. lenti ♀ x T. melanica ♂ showed a specific pattern of T. lenti, T. lenti and T. melanica, respectively. Thus, the pattern of segregation of morphological characteristics between species of the T. brasiliensis complex was characterized. These results highlight the importance of integrative taxonomy for the correct identification of Chagas disease vectors grouped in the T. brasiliensis complex if natural hybridization events occur. Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rodovia Araraquara-Jaú km 1 Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Rua Cristóvão Colombo 2265, Letras e Ciências Exatas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rodovia Araraquara-Jaú km 1 Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Rua Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Júnior Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Rua Cristóvão Colombo 2265, Letras e Ciências Exatas FAPESP: 2017/05015-7 CNPq: 307398/2018-8

Made available in DSpace on 2020-12-12T02:13:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 The parasite-vector interaction of Chagas disease is still poorly understood and the understanding of this relationship can help in the development of new strategies to control Trypanosoma cruzi transmission, which is the etiological agent of this disease. Considering the need to know if T. cruzi can cause some pathology in the reproductive system of the Chagas disease vectors, we investigated the spermatogenesis of Triatoma infestans infected by T. cruzi through histological and cytogenetic analysis. Trypanosoma cruzi Bolivia strain infection was not pathogenic for the reproductive system of T. infestans, because all the analyzed males had normal spermatogenesis, with all phases (spermatocytogenesis, meiosis and spermiogenesis) happening without any change. Thus, we demonstrated that the presence of T. cruzi Bolivia strain does not have influence in the spermatogenesis of T. infestans and we suggest that the influences on reproductive system observed for other species were a result of the action of the parasite on gametogenesis of females. Laboratório de Biologia Celular Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório de Parasitologia Departamento de Ciências Biológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1 Laboratório Multiusuário de Microscopia e Microanálise Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório de Citogenética e Molecular de Insetos Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório de Biologia Celular Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório de Parasitologia Departamento de Ciências Biológicas Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Faculdade de Ciências Farmacêuticas, Rodovia Araraquara-Jaú km 1 Laboratório Multiusuário de Microscopia e Microanálise Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265 Laboratório de Citogenética e Molecular de Insetos Departamento de Biologia Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) Instituto de Biociências Letras e Ciências Exatas, Rua Cristóvão Colombo 2265

The genus Psammolestes within the subfamily Triatominae and tribe Rhodniini comprises the species Psammolestes arthuri, Psammolestes coreodes, and Psammolestes tertius, all potential vectors of Chagas disease. A feature of Psammolestes is their close association with birds, which makes them an interesting model for evolutionary studies. We analyzed cytogenetically Psammolestes spp., with the aim of contributing to the genetic and evolutionary knowledge of these vectors. All species of the Psammolestes showed the same chromosomal characteristics: chromocenter formed only by sex chromosomes X and Y, karyotype 2n = 22 and constitutive heterochromatin, and AT base pairs restricted to the sex chromosome Y. These results corroborate the monophyly of the genus and lead to the hypothesis that during the derivation of P. tertius, P. coreodes, and P. arthuri from their common ancestor, there was no reorganization in the number or structure of chromosomes.

Chagas disease is a public health problem caused by the Trypanosoma cruzi, and the T. cruzi I (TcI) and T. cruzi II (TcII) groups are considered important genotypes from the clinical point of view. Currently, the groups need to be molecularly analyzed for their identification; thus, we cytogenetically analyzed these groups with the objective of developing more accessible techniques for the characterization of these parasites. TcI and TcII groups were differentiated by nucleus characterization with lacto-acetic orcein (TcI-nucleus with positive heteropycnosis and TcII-nucleus with negative heteropycnosis), emphasizing the importance of the application of this technique for epidemiological and clinical studies of Chagas disease.

The subfamily Triatominae currently consists of 154 species, most of them being of great importance for public health because they are considered potential vectors of the protozoan Trypanosoma cruzi, the etiologic agent of Chagas disease. In addition to their epidemiological importance, these insects are considered important biological models for cell studies because they have peculiar characteristics in their cells, for example, persistence of the nucleolus during spermatogenesis. This phenomenon is characterized by the presence of the nucleolus or nucleolar corpuscles during all phases of meiosis. To date, all knowledge is restricted to the study of the presence/absence of the nucleolus during the triatomine meiosis, so the present work aimed to analyze if this persistent nucleolar material has transcriptional activity. Analysis of the meiotic metaphases of Rhodnius montenegrensis and Panstrongylus megistus by using fluorochrome acridine orange made it possible to characterize the presence of RNA in the nucleolar material. Thus, it was demonstrated, for the first time, that the persistent nucleolar material during triatomine meiosis is transcriptionally active, supporting the hypothesis of the relationship between nucleolar persistence during meiosis of these insects and the formation of the chromoid body, an organelle responsible for the support of all transcriptional activities during spermiogenesis.

Triatomines are vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease. Although the evolutionary process in triatomine is considered as disruptive, cryptic speciation and homoploid hybridization also are possible modes of speciation. Several analyses suggested Triatoma brasiliensis macromelasoma as a product of hybridization between T. brasiliensis and Triatoma juazeirensis. Thus, we analyzed genetic characteristics (chromosomal analysis, genetic distance for the mitochondrial ND1 gene, and the pattern of bands of internal transcribed spacer [ITS]-1) of these species, with emphasis on the phenomenon of homoploid hybridization. All species showed the same cytogenetic characteristics, low genetic distance for ND1 gene, and the same pattern of ITS-1 bands. We consider that these genetic characteristics, together with the large chromatic polymorphism and the viability of experimental crosses possibly are due to the processes of introgression that these species suffered during the process of homoploid hybridization.

Chagas disease is a public health problem caused by the protozoan Trypanosoma cruzi that affects about 8 million people worldwide. The main form of transmission of T. cruzi is vectorial, through triatomines feces contaminated with the parasite. All species are considered as potential vectors of T. cruzi. The main identification keys of these vectors are based only on morphological characters. However, there are very similar or even same species (cryptic species) that may lead to wrong classification of the vectors. Therefore, we developed an identification key using cytogenetic data, to aid and help the correct classification of triatomines. From the cytogenetic characters, identification keys were created for the five Brazilian states (Alagoas, Amapá, Ceará, Roraima, and Santa Catarina). These data are important because the correct classification of triatomines helps directly the activity of the vector control programs.

Triatomines are hematophagous insects of great epidemiological importance, since they are vectors of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. Triatoma brasiliensis complex is a monophyletic group formed by two subspecies and six species: T. b. brasiliensis, T. b. macromelasoma, T. bahiensis, T. juazeirensis, T. lenti, T. melanica, T. petrocchiae and T. sherlocki. The specific status of several species grouped in the T. brasiliensis complex was confirmed from experimental crossing and analysis of reproductive barriers. Thus, we perform interspecific experimental crosses between T. lenti and other species and subspecies of the T. brasiliensis complex and perform morphological analysis of the gonads and cytogenetic analysis in the homeologous chromosomes of the hybrids of first generation (F1). Besides that, we rescue all the literature data associated with the study of reproductive barriers in this monophyletic complex of species and subspecies. For all crosses performed between T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis and T. melanica with T. lenti, interspecific copulas occurred (showing absence of mechanical isolation), hybrids were obtained, none of the male hybrids presented the phenomenon of gonadal dysgenesis and 100% pairing between the chromosomes homeologous of the hybrids was observed. Thus, we demonstrate that there are no pre-zygotic reproductive barriers installed between T. lenti and the species and subspecies of the T. brasiliensis complex. In addition, we demonstrate that the hybrids obtained between these crosses have high genomic compatibility and the absence of gonadal dysgenesis. These results point to reproductive compatibility between T. lenti and species and subspecies of the T. brasiliensis complex (confirming its inclusion in the complex) and lead us to suggest a possible recent diversification of the taxa of this monophyletic group.

Triatoma vitticeps is a Chagas disease vector that was found infected with Trypanosoma cruzi in homes. As this species is endemic from Brazil (Bahia, Espírito Santo, Minas Gerais, and Rio de Janeiro) and no study comparing the specimens from different Brazilian states was conducted, we analyzed the genetic distance (16S rDNA, Cyt b, and COI mitochondrial genes) and the chromosomal characteristics for T. vitticeps from Minas Gerais, Rio de Janeiro, and Espírito Santo. All specimens showed the same cytogenetic characteristics. On the other hand, the different mitochondrial genes demonstrated high intraspecific variation between the genetic distances of T. vitticeps from different states ranging from 2.3% to 7.2%. Based on this, our results suggest that possibly what is characterized as T. vitticeps is a complex of cryptic species (or subspecies).

Six to seven million people worldwide are estimated to be infected with Trypanosoma cruzi, the etiologic agent of Chagas disease transmitted mainly by triatomines. Triatoma bahiensis was recently collected in the Brazilian state of Bahia and revalidated using different approaches. The main criterion used to define a “good” biological species is reproductive isolation, so we evaluated the cytogenetics of first-generation (F1) hybrids resulting from the experimental cross between T. bahiensis females and Triatoma lenti males to possibly characterize the postzygotic isolation associated with the hybrid breakdown. All cells analyzed presented a karyotype of 2n = 22 and a pair of univalent autosomes. This chromosome behavior represents hybrid collapse and underscores the specific status of T. bahiensis. Thus, we have characterized the presence of the hybrid collapse phenomenon in an experimental cross, and we confirm the specific status of T. bahiensis, thus contributing to the Triatominae taxonomy.

Made available in DSpace on 2020-12-12T01:43:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Triatoma genus is paraphyletic, and its species are grouped into complexes and subcomplexes. Given the fact that species that make up a given subcomplex generally share chromosomal traits, we analyzed the distribution of AT- and CG-rich DNA of the T. brasiliensis species subcomplex, in order to establish affinities among members of the T. brasiliensis subcomplex based on chromatin and chromosome traits and develop an identification key for the four monophyletic Triatoma subcomplexes from South America. All species exhibited a CG-rich X sex chromosome and autosomes, as well as an AT-rich Y sex chromosome. This feature can be used as a diagnostic characteristic to determine whether a given species is a member of the T. brasiliensis subcomplex, because it enables the differentiation of these species from all Triatoma of South America. Thus, we confirmed the chromosomal relationship of the T. brasiliensis species subcomplex and developed a dichotomous key based on the chromocenter to differentiate the species from this subcomplex from the other monophyletic Triatoma subcomplexes from South America. Laboratório de Parasitologia Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” FCFAR/UNESP, Rodovia Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” IBILCE/UNESP, Rua Cristóvão Colombo 2265 Instituto de Biologia Universidade Estadual de Campinas IB/UNICAMP, Rua Monteiro Lobato, 255 Laboratório de Ecologia Animal Departamento de Engenharia e Meio Ambiente Centro de Ciências Aplicadas e Educação Universidade Federal de Paraíba CCAE/UFPB, Av. Santa Elizabete, 160 Laboratório de Parasitologia Departamento de Ciências Biológicas Faculdade de Ciências Farmacêuticas Universidade Estadual Paulista “Júlio de Mesquita Filho” FCFAR/UNESP, Rodovia Araraquara-Jaú km 1 Laboratório de Biologia Celular Departamento de Biologia Instituto de Biociências Letras e Ciências Exatas Universidade Estadual Paulista “Júlio de Mesquita Filho” IBILCE/UNESP, Rua Cristóvão Colombo 2265 FAPESP: 2013/19764-0 FAPESP: 2017/21359-8

Chagas disease is a public health problem caused by the Trypanosoma cruzi, and the T. cruzi I (TcI) and T. cruzi II (TcII) groups are considered important genotypes from the clinical point of view. Currently, the groups need to be molecularly analyzed for their identification; thus, we cytogenetically analyzed these groups with the objective of developing more accessible techniques for the characterization of these parasites. TcI and TcII groups were differentiated by nucleus characterization with lacto-acetic orcein (TcI—nucleus with positive heteropycnosis and TcII—nucleus with negative heteropycnosis), emphasizing the importance of the application of this technique for epidemiological and clinical studies of Chagas disease.

Chagas disease is caused by the protozoan Trypanosoma cruzi. This disease is distributed in 21 Latin American countries, where it is mostly vector-borne. In Brazil, there are 68 triatomine species. To date, the epidemiological surveys indicate that the state of Sao Paulo presents 11 species of triatomines, and most of these species have already been collected in a home environment and found to be infected with T. cruzi. Problems in correctly identifying species can lead to incorrect panorama of distribution of Chagas disease vectors. Thus, we developed an identification key for the triatomines of the state of Sao Paulo, based on cytogenetic data. With the exception of Panstrongylus diasi that does not present cytogenetic data available in the literature, all species were differentiated by cytogenetic characteristics. We emphasize the importance of using this key as a simple and objective tool in the entoepidemiological surveys conducted by the vector control programs.

Triatoma sordida is among the main Brazilian species considered as Chagas disease vectors. The genetic studies are directed mainly to phylogenetic questions because this species possibly have suffered cryptic speciation. Furthermore, there are few studies that analyzed the structure and genetic variability of specimens from Brazil and that showed low genetic diversity and strong genetic structuring of the population samples. Therefore, because of great epidemiological importance of T. sordida and mainly the restriction of genetic characterization of this vector only for populations of Minas Gerais state, this article performs a genetic analysis of the T. sordida from seven different Brazilian states (representing different biomes), by means of cytogenetic markers. All analyzed specimens presents the same cytogenetic characteristics: early meiotic prophase with several heterochromatic bodies dispersed in the nucleus (CG-rich), being one of them formed by the associated sex chromosomes surrounded by some autosomal heterochromatic regions, meiotic metaphase with most autosomal pairs exhibiting a C-heterochromatic block in one chromosomal end (CG-rich), Y sex chromosome fully heterochromatin (AT-rich), and X chromosome may present a small C-block (CG-rich). These results are important because the chromosomal markers enable to confirm and expand the low genetic diversity for all Brazilian states occupied by T. sordida, suggesting that all Brazilian populations were originated from a small ancestral population and possibly dispersed to other biomes by founder effect. In addition, we suggest that T. sordida from Brazil are not suffering cryptic speciation and we confirm the classification of all Brazilian examples as T. sordida sensu stricto.

The brasiliensis complex is composed of five triatomine species, and different approaches suggest that Triatoma lenti and Triatoma petrochiae may be the new members. Therefore, this study sought to analyze the phylogenetic relationships within this complex by means of the D2 region of the 28S RNA gene, and to analyze the degree of polymorphism and phylogenetic significance of this gene for South American triatomines. Phylogenetic analysis by using sequence fragments of the D2 domain did not allow to perform phylogenetic inferences on species within the brasiliensis complex, because the gene alignment composed of a matrix with 37 specimens exhibited only two variable sites along the 567 base pairs used. Furthermore, if all South American species are included, only four variable sites were detected, reflecting the high degree of gene conservation. Therefore, we do not recommend the use of this gene for phylogenetic reconstruction for this group of Chagas disease vectors.

Triatoma rubrofasciata (De Geer) (Hemiptera, Triatominae) was the first Triatominae species formally described, as Cimex rubrofasciatus De Geer, 1773. This insect presents anthropogenic habits (Galvao 2014) and is considered of global epidemiological importance, since it has a pantropical distribution and was found infected with the protozoan Trypanosoma cruzi (Chagas, 1909) (Sherlock & Serafim 1974; Brazil & Silva 1983), the etiological agent of Chagas disease.

Made available in DSpace on 2018-12-11T17:03:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-02 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The genus Zaprionus consists of approximately 60 species of drosophilids that are native to the Afrotropical region. The phylogenetic position of Zaprionus within the Drosophilidae family is still unresolved. In the present study, ultrastructural features of spermatozoa of 6 species of Zaprionus as well as the species Drosophila willistoni and Scaptodrosophila latifasciaeformis were analyzed. The ultrastructure revealed that the species have the same flagellar ultrastructure. Two mitochondrial derivatives, one larger than the other, close to the axoneme were present, primarily in D. willistoni (subgenus Sophophora). Except for Z. davidi and Z. tuberculatus, the analyzed species had paracrystalline material in both mitochondrial derivatives. Moreover, the testes showed 64 spermatozoa per bundle in all of the species. In the cluster analysis, 6 Zaprionus species were grouped closely, but there were some incongruent positions in the cladogram. The results indicated that sperm ultrastructure is an important tool for elucidating the phylogeny and taxonomy of insects. Laboratory of Genetics Ecology and Evolution of Drosophila Department of Biology Institute of Biosciences Humanities and the Exact Sciences São Paulo State University – Júlio de Mesquita Filho (UNESP/IBILCE), São José do Rio Preto Laboratory of Cell Biology Department of Biology Institute of Biosciences Humanities and the Exact Sciences São Paulo State University – Júlio de Mesquita Filho (UNESP-IBILCE), São José do Rio Preto Laboratory of Genetics Ecology and Evolution of Drosophila Department of Biology Institute of Biosciences Humanities and the Exact Sciences São Paulo State University – Júlio de Mesquita Filho (UNESP/IBILCE), São José do Rio Preto Laboratory of Cell Biology Department of Biology Institute of Biosciences Humanities and the Exact Sciences São Paulo State University – Júlio de Mesquita Filho (UNESP-IBILCE), São José do Rio Preto

Spermatogenesis is composed of three distinct phases: spermatocytogenesis, which is the proliferation phase; meiosis, which is the division phase; and spermiogenesis, which is the differentiation phase (Johnson et al. 1997). In insects the spermatogenesis is cystic (Dumser 1980). In cystic spermatogenesis, the meiotic divisions are synchronous within a given cyst (Smith 1916). This phenomenon has been confirmed in the subfamily Triatominae (Silistino-Souza et al. 2011; Alevi et al. 2015).

Laboratorio de Parasitologia, Departamento de Ciencias Biologicas, Faculdade de Ciencias Farmaceuticas – FCFAR, Universidade Estadual Paulista “Julio de Mesquita Filho” – UNESP, Rodovia Araraquara-Jau, Km 1, CEP 14801-902, Araraquara, SP, Brazil*e-mail: kaiochaboli@hotmail.comReceived: December 15, 2015 – Accepted: June 2, 2016 – Distributed: November 31, 2017

The genus Psammolestes within the subfamily Triatominae and tribe Rhodniini comprises the species Psammolestes arthuri, Psammolestes coreodes, and Psammolestes tertius, all potential vectors of Chagas disease. A feature of Psammolestes is their close association with birds, which makes them an interesting model for evolutionary studies. We analyzed cytogenetically Psammolestes spp., with the aim of contributing to the genetic and evolutionary knowledge of these vectors. All species of the Psammolestes showed the same chromosomal characteristics: chromocenter formed only by sex chromosomes X and Y, karyotype 2n = 22 and constitutive heterochromatin, and AT base pairs restricted to the sex chromosome Y. These results corroborate the monophyly of the genus and lead to the hypothesis that during the derivation of P. tertius, P. coreodes, and P. arthuri from their common ancestor, there was no reorganization in the number or structure of chromosomes.

El uso de características sutiles como características de diagnóstico de especies en taxones con una gran similitud morfológica a veces falla en discriminar la variación intraespecífica de las diferencias interespecíficas, lo que lleva a una delimitación incorrecta de la especie. Una evaluación clara de los límites de las especies es particularmente relevante en los organismos vectores de enfermedades para comprender los procesos epidemiológicos y evolutivos que afectan la capacidad de transmisión. Aquí, evaluamos la validez del Rhodnius taquarussuensis recientemente descrito (da Rosa et al., 2017) utilizando cruces interespecíficos y marcadores moleculares. No detectamos diferencias en las tasas de eclosión en cruces interespecíficos entre R. taquarussuensis y R. negligencias (Lent, 1954). Además, los análisis de divergencia genética y delimitación de especies muestran que R. taquarussuensis no es un linaje independiente en el grupo R. prolixus. Estos resultados sugieren que R. taquarussuensis es una forma fenotípica de R. negligenciaus en lugar de una especie distinta. Nos gustaría enfatizar que se necesitan diferentes fuentes de evidencia para delimitar correctamente las especies. Consideramos que este es un paso importante en la comprensión de la propagación y transmisión vectorial de la enfermedad de Chagas. The use of subtle features as species diagnostic traits in taxa with high morphological similarity sometimes fails in discriminating intraspecific variation from interspecific differences, leading to an incorrect species delimitation. A clear assessment of species boundaries is particularly relevant in disease vector organisms in order to understand epidemiological and evolutionary processes that affect transmission capacity. Here, we assess the validity of the recently described Rhodnius taquarussuensis (da Rosa et al., 2017) using interspecific crosses and molecular markers. We did not detect differences in hatching rates in interspecific crosses between R. taquarussuensis and R. neglectus (Lent, 1954). Furthermore, genetic divergence and species delimitation analyses show that R. taquarussuensis is not an independent lineage in the R. prolixus group. These results suggest that R. taquarussuensis is a phenotypic form of R. neglectus instead of a distinct species. We would like to stress that different sources of evidence are needed to correctly delimit species. We consider this is an important step in understanding vectorial Chagas disease spread and transmission. © 2019 Nascimento et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.