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Background Triatoma tibiamaculata is a species distributed in ten Brazilian states which has epidemiological importance as it has already been found infecting household areas. The taxonomy of this triatomine has been quite unstable: it was initially described as Eutriatoma tibiamaculata. Later, the species was transferred from the genus Eutriatoma to Triatoma. Although included in the genus Triatoma, the phylogenetic position of T. tibiamaculata in relation to other species of this genus has always been uncertain once this triatomine was grouped in all phylogenies with the genus Panstrongylus, rescuing T. tibiamaculata and P. megistus as sister species. Thus, we evaluated the generic status of T. tibiamaculata using phylogenetic and chromosomal analysis. Methods Chromosomal (karyotype) and phylogenetic (with mitochondrial and nuclear markers) analyses were performed to assess the relationship between T. tibiamaculata and Panstrongylus spp. Results The chromosomal and phylogenetic relationship of T. tibiamaculata and Panstrongylus spp. confirms the transfer of the species to Panstrongylus with the new combination: Panstrongylus tibiamaculatus. Conclusions Based on chromosomal and phylogenetic characteristics, we state that P. tibiamaculatus comb. nov. belongs to the genus Panstrongylus and that the morphological features shared with Triatoma spp. represent homoplasies. Graphical Abstract

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 2022-04-29T08:30:20Z (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

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.

The Triatominae subfamily is comprised of 18 genera and six tribes. The tribe Rhodniini is comprised of two genera (Rhodnius and Psammolestes). Nucleolar persistence is defined by the presence of the nucleolus or nucleolar corpuscles during the meiotic metaphase. To date, this phenomenon has been described for 13 species of triatomine that are included in the genera Triatoma, Rhodnius, and Panstrongylus. Thus, because the phenomenon of nucleolar persistence has been described in only two species of the genus Rhodnius, we have analyzed the nucleolar behavior during spermatogenesis of eight species of the genus Rhodnius (R. colombiensis, R. montenegrensis, R. nasutus, R. neglectus, R. neivai, R. pictipes, R. prolixus, and R. robustus), with a focus on nucleolar persistence. By means of cytogenetic analysis with silver ions, nucleolar behavior during spermatogenesis is described in the eight species of Rhodnius analyzed. In all of them nucleolar behavior was similar and the phenomenon of nucleolar persistence was often observed. Therefore, we confirm nucleolar persistence as a peculiarity of the genus Rhodnius. However, it is emphasized that new cytogenetic analysis should be performed in the Triatominae subfamily, more specifically among the 15 genera that do not exhibit the nucleolar behavior described, in order to assess whether this phenomenon is truly a synapomorphy of these hematophagous insects.

The tribe Rhodniini is a monophyletic group composed of 22 species, with 19 in the Rhodnius genus and three in the Psammolestes genus. These insects are morphologically very similar (cryptic species), and new tools are important for investigating the taxonomy of these vectors. Spermiotaxonomy is an important tool in differentiating between related species, and this study analyzed the spermatids of Rhodniini species to elucidate their spermiotaxonomy. All of the Rhodniini species contained two heteropyknotic filaments in the extremities of their cells. Although spermiotaxonomy has been an important tool in differentiating between species of the Triatoma genus, all of the species in the Rhodnius genus exhibited the same characteristics in their male gametes. However, spermatid analysis made it possible to confirm the monophyly of the Rhodniini tribe, because Psammolestes tertius had the same pattern as that described for Rhodnius. The results of this study demonstrate that spermiotaxonomy, in addition to being an important tool for differentiating between related species of Triatoma, can be used as an optimization tool in phylogenetic analyses.

All species of triatomines are considered potential vectors of Chagas disease and the reproductive biology of these bugs has been studied by different approaches. In 1999, nucleolar persistence during meiosis was observed in the subfamily for the first time. Recently, it has been observed that all species within the genus Rhodnius exhibit the same phenomenon, suggesting that it may be a synapomorphy of the triatomines. Thus, this article aims to analyze the nucleolar behavior during spermatogenesis of 59 triatomine species. All analyzed species exhibited nucleolar persistence during meiosis. Recently, it has been suggested that nucleolar persistence may be fundamental for the spermatogenesis of these vectors, since it is related to the formation of the chromatoid body. Therefore, we emphasize that this phenomenon is a peculiarity of the Triatominae subfamily and that further studies are required to analyze whether the nucleolar material that persists is active.