Biology subjects

Vivero, R.

Publications and source records attributed to Vivero, R..

3 recordsLinked to original sources

bioRxiv2025

Sex differentiation, divergence, and introgression in the leishmaniasis vector Lutzomyia longipalpis

An estimated one billion people are at risk of acquiring the disease leishmaniasis annually. This disease, among others, is transmitted to humans via sandfly vectors of the family Psychodidae. In the Neotropics, Lutzomyia longipalpis is one of the most common vectors of leishmaniasis, but little is known about its genetics and population structure, hampering control efforts. We generated sex-specific genome assemblies of Lu. longipalpis from Colombia, and examined population genomics of this species. We found that sex accounts for [~]11% of genome-wide variation, primarily driven by differentiation between the sexes in an XY sex chromosome. Analyses of transposable elements indicate that the size difference in the sex chromosome is driven by more transposable elements in the male chromosome. Further, we examined population genomics and structure across the South American continent. We identified significant genetic divergence between Colombian and Brazilian sandflies and population structure within Lu. longipalpis sensu lato samples collected from the same sites in Brazil. These results strongly suggest the presence of multiple, sympatric species within a cryptic species complex, concordant with other published phenotypic evidence. SIGNIFICANCELeishmaniasis has emerged as an important public health issue. Transmission occurs exclusively through Phlebotomine sandflies of the genera Lutzomyia and Phlebotomus, yet our ability to prevent its spread is constrained by limited knowledge of the biological and ecological factors that make these insects effective vectors. In this manuscript, we leverage whole-genome sequencing to investigate the evolutionary forces shaping genetic diversity in Lutzomyia longipalpis, a key vector of leishmaniasis.

genomics↗

bioRxiv2022

Diversity of cave Phlebotomines (Diptera: Psychodidae) from a Colombian cave

Sandflies are vector species of Leishmania, among many other pathogens, with a global distribution and a variety of ecological niches. Previous samplings have found that karstic formations (i.e., caves and folds formed by the erosion of limestone) serve as a natural habitat to sandfly species. The majority of samplings of cave sandfly diversity have occurred in Brazil and to date none have studied the species composition in a cave in the Northern Andes. We collected sandflies in the Cave "Los Guacharos", in the state of Antioquia, Colombia. The sampling was carried out during two consecutive nights in September 2019. CDC-type light traps were installed inside the cavern and in other surrounding karst systems (caves and folds). In total, we identified 18 species of sandfly from the cave and surrounding karst systems, including three new records for Colombia (Bichromomyia olmeca nociva, Brumptomyia brumpti, and Warileya leponti), and provide the first karstic reports for four other species (Lutzomyia gomezi, Lutzomyia hartmanni, Pintomyia ovallesi, and Psychodopygus panamensis). We then used the results of our survey and published literature to test two hypotheses. First, that sandfly diversity in Neotropical caves is richest nearer to the equator and second that there is a phylogenetic signal of karstic habitat use in sandflies. Counter to our predictions, we found no evidence that diversity follows a latitudinal gradient. Further, we find no evidence of a phylogenetic signal of karstic habitat use, instead finding that the use of caves likely evolved multiple times across several genera. Our results highlight the importance of a wide sampling to understand the natural habitat of sandflies and other disease vectors.

zoology↗

bioRxiv2022

Climatic niche conservatism in a clade of disease vectors (Diptera: Phlebotominae)

Sandflies of the family Psychodidae show notable diversity in both disease vector status and climatic niche. Some species (in the subfamily Phlebotominae) transmit Leishmania parasites, responsible for the disease leishmaniasis. Other Psychodidae species do not. Psychodid species ranges can be solely tropical, confined to the temperate zones, or span both. Studying the relationship between the evolution of disease vector status and that of climatic niche affords an understanding not only of the climate conditions associated with the presence and species richness of Leishmania vectors, but also allows the study of the extent to which psychodid flies climatic niches are conserved, in a context with implications for global human health. We obtained observation site data, and associated climate data, for 223 psychodid species to understand which aspects of climate most closely predict distribution. Temperature and seasonality are strong determinants of species occurrence within the clade. We built a mitochondrial DNA phylogeny of Psychodidae, and found a positive relationship between pairwise genetic distance and climate niche differentiation, which indicates strong niche conservatism. This result is also supported by strong phylogenetic signals of metrics of climate differentiation. Finally, we used ancestral trait reconstruction to infer the tropicality (i.e., proportion of latitudinal range in the tropics minus the proportion of the latitudinal range in temperate areas) of ancestral species, and counted transitions to and from tropicality states, finding that tropical and temperate species respectively produced almost entirely tropical and temperate descendant species, a result consistent for vector and non-vector species. Taken together, these results imply that while vectors of Leishmania can survive in a variety of climates, their climate niches are strongly predicted by phylogeny.

evolutionary biology↗