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1. Introduction The order Decapoda constitutes a large representative group in the extensive and specious subphylum Crustacea. Chace (1951), Martin and Davis (2001), De Grave et al. (2009), and De [...], Genome size (GS) or DNA nuclear content is considered a useful index for making inferences about evolutionary models and life history in animals, including taxonomic, biogeographical, and ecological scenarios. However, patterns of GS variation and their causes in crustaceans are still poorly understood. This study aimed to describe the GS of five Neotropical Synalpheus non-gambarelloides shrimps (S. apioceros, S. minus, S. brevicarpus, S. fritzmueller, and S. scaphoceris) and compare the C-values of all Caridea infraorder in terms of geography and phylogenetics. All animals were sampled in the coast of Sao Paulo State, Brazil, and GS was assessed by flow cytometry analysis (FCA). The C-values ranged from 7.89 pg in S. apioceros to 12.24 pg in S. scaphoceris. Caridean shrimps had higher GS than other Decapoda crustaceans. The results reveal a tendency of obtaining larger genomes in species with direct development in Synalpheus shrimps. In addition, a tendency of positive biogeographical (latitudinal) correlation with Caridea infraorder was also observed. This study provides remarkable and new protocol for FCA (using gating strategy for the analysis), which led to the discovery of new information regarding GS of caridean shrimps, especially for Neotropical Synalpheus, which represents the second-largest group in the Caridea infraorder. Key words: C-value, snapping shrimp, Decapoda, DNA content La taille du genome ou le contenu en ADN nucleaire est considere comme un indice utile pour faire des inferences au sujet des modeles evolutifs et de l'histoire de vie chez les animaux, incluant des scenarios taxonomiques, biogeographiques et ecologiques. Cependant, les types de variation quant a la taille des genomes ainsi que leurs causes sont encore mal compris chez les crustacees. Cette etude visait a decrire la variation pour la taille du genome chez cinq especes de crevettes neotropicales Synalpheus nongambarelloides (S. apioceros, S. minus, S. brevicarpus, S. fritzmueller et S. scaphoceris) et de comparer les valeurs C au sein du sous-ordre Caridea en termes de geographie et de phyllogenetique. Tous les specimens ont ete captures sur la cote de l'etat de Sao Paulo au Bresil et la taille du genome a ete mesuree par cytometrie en flux (FCA). Les valeurs C variaient entre 7,89 pg chez le S. apioceros et 12,24 pg chez le S. scaphoceris. Les crevettes carideennes presentaient des genomes de plus grande taille que les autres crustacees de l'ordre des Decapoda. Les resultats ont revele une tendance a l'accroissement de la taille des genomes chez les crevettes du genre Synalpheus presentant un developpement direct. De plus, les auteurs ont egalement note une correlation biogeographique positive (latitudinale) au sein du sous-ordre Caridea. Cette etude rapporte un nouveau protocole remarquable pour l'analyse FCA (faisant appel a une strategie d'analyse hierarchique), lequel a permis de faire des observations inedites au sujet de la taille du genome chez les crevettes carideennes, specifiquement chez des especes neotropicales du genre Synalpheus, lequel represente le second plus grand groupe au sein du sous-ordre Caridea. [Traduit par la Redaction] Mots-cles : valeur C, crevettes pistolet, Decapoda, contenu en ADN

Species of the Rhodnius genus have a complex taxonomy because the events of phenotypic plasticity and cryptic speciation make it difficult to correctly classify these vectors. During the taxonomic history of the genus, five synonymization events occurred. Additionally, some authors suggest that R. milesi possibly represent only phenotypic polymorphisms of R. neglectus. Thus, we analyzed the specific status of R. milesi in relation to R. neglectus using phylogenetic studies with the mitochondrial gene cytochrome B and the study of reproductive barriers. The phylogenetic reconstruction grouped R. milesi together with R. neglectus from different localities, demonstrating that these taxa represent the same species based on the phylogenetic species concept. Experimental crosses demonstrate the absence of pre- and postzygotic barriers under laboratory conditions. Additionally, when the hatch rates of crosses are compared to intraspecific crosses, it can be noted that they are high and very similar. Finally, the mortality rate of the hybrids does not indicate hybrid inviability, the absence of chromosome pairing errors does not indicate hybrid sterility, and the proportion between male and female hybrids demonstrates that Haldane's rule was not acting. Therefore, we perform the formal synonymization of R. milesi with R. neglectus. [ABSTRACT FROM AUTHOR]

Considering that health professionals at Brazil had doubts about the entomoepidemiological issues of Chagas disease (CD), and that many of them highlighted not feeling totally safe for clinical care, the knowledge of 281 Brazilian medical students was evaluated through a cross-sectional, descriptive, prospective, and quantitative research. Most students demonstrated that they knew about the etiological agent of CD (Trypanosoma cruzi), since 279 students answered the questionnaire correctly. Furthermore, the medical students demonstrated knowledge of the main form of transmission of the parasite, as 278 students associated CD transmission with triatomines. On the other hand, approximately 25 students did not associate CD transmission with triatomine feces. Besides that, these future health professionals had difficulties in relation to the treatment of CD, as more than half of the students (176) wrongly answered that CD "is not curable" or "is curable in the chronic phase". Based on the results obtained that point out the difficulties medical students have with CD, there is a need for undergraduate medical courses to address the neglected diseases holistically because the National Curriculum Guidelines for the medical course require the training of competent health professionals capable of integrating the biological, psychological, social, and environmental dimensions. [ABSTRACT FROM AUTHOR]

Triatomines are insects of great importance for public health, as they are vectors of protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. The genus Triatoma is the most representative in number of species and one of the most important from an epidemiological point of view. The Triatoma pseudomaculata subcomplex (composed of the species Triatoma arthurneivai, T. pseudomaculata, and T. wygodzinskyi [from the old subcomplex Triatoma maculata] and Triatoma baratai, Triatoma costalimai, Triatoma deaneorum, Triatoma jatai, and Triatoma williami [from the old Triatoma matogrossensis subcomplex]) was recently proposed based on chromosomal data. Thus, considering that the experimental crossings helped with systematic questions about triatomines, we performed crosses between the species of the T. pseudomaculata subcomplex. Thus, we crossed T. pseudomaculata and Triatoma costalimai to assess the possible presence of interspecific genomic and reproductive compatibility. In addition, based on the molecular data available on GenBank, we performed a phylogenetic systematics study to assess the evolutionary relationship of the species of the T. pseudomaculata subcomplex. Experimental crosses did not result in hybrids, demonstrating that there is a prezygotic barrier established between these species. Based on the above, we confirmed the specific status of T. pseudomaculata and T. costalimai based on the biological species concept. Furthermore, the reproductive incompatibility associated with the phylogenetic systematic analyses demonstrate that T. costalimai does not belong to the T. pseudomaculata subcomplex. Thus, we suggest that the sister species T. costalimai and T. jatai should be grouped into a new subcomplex called T. costalimai.

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.