Navegando por Autor "Vasconcelos, Santelmo"

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Artigo
Before it’s too late: priority areas for conservation of cryptic and threatened species of troglobitic arthropods in the Brazilian semiarid
(2024-04-18) Bento, Diego de Medeiros; Ferreira, Rodrigo Lopes; Vasconcelos, Santelmo; Lima, Jamily Lorena Ramos de; Oliveira, Guilherme; Silva, Tiago Castro; Lima, Sergio Maia Queiroz
One of the most important steps in identifying priority areas for conservation is the assessment of species richness and their extinction risks. While most species remain undescribed, the identification of cryptic lineages is frequent in phylogenetic and phylogeographic studies. This is particularly common in troglobites, exclusively subterranean organisms. The Jandaíra Formation, in the Brazilian semiarid, combines the occurrence of extensive karstic areas with hundreds of caves and subterranean aquifers in a region with intense paleoclimatic changes. This region is recognized for the richness of troglobitic species, some of which are widely distributed in heterogeneous areas. This suggests cryptic lineages that can be differentially exposed to anthropogenic threats, with distinct extinction risks regarding the nominal taxa of which they putatively belong. To test it, a large sampling was conducted and, by means of lineage delimitation analyses, the genetic structure of four troglobitic taxa, three aquatic and one terrestrial, was evaluated. In addition, the extinction risk of these lineages was assessed and priority areas for conservation were identified. The results indicated that while Cirolanidae sp. 1 (Isopoda) is a single species widely distributed, Cirolanidae sp. 2, Potiberaba porakuara (Amphipoda) and Kinnapotiguara troglobia (Hemiptera) present an extensive diversity of cryptic and endemic lineages, most of which are likely new threatened species. Furthermore, two priority areas for conservation of these lineages were identified. Thus, comparative phylogeography may represent a first step in the conservation of subterranean taxa, indicating areas that should be prioritized in a context of increasing threats and dwindling conservation resources.
Artigo
Complete mitochondrial genomes of three vulnerable cave bat species and their phylogenetic relationships within the order Chiroptera
(2024-08-22) Molina, Michele; Oliveira, Guilherme; Oliveira, Renato R. M.; Nunes, Gisele L.; Pires, Eder S.; Prous, Xavier; Ribeiro, Mariane; Vasconcelos, Santelmo
The IUCN Red List of Threatened Species contains 175 Brazilian bat species that are threatened by extinction in some degree. From this perspective, it is essential to expand the knowledge about the genetic diversity of vulnerable bats. Genomic sequencing can be useful to generate robust and informative genetic references, increasing resolution when analyzing relationships among populations, species, or higher taxonomic levels. In this study, we sequenced and characterized in detail the first complete mitochondrial genomes of Furipterus horrens, Lonchorhina aurita, and Natalus macrourus, and investigated their phylogenetic position based on amino acid sequences of protein-coding genes (PCGs). The mitogenomes of these species are 16,516, 16,697, and 16,668 bp in length, respectively, and each comprises 13 PCGs, 22 tRNA genes, two rRNA genes, and a putative control region (CR). In the three species, genes were arranged similarly to all other previously described bat mitogenomes, and nucleotide composition was also consistent with the reported range. The length and arrangement of rrnS and rrnL were also consistent with those of other bat species, showing a positive AT-skew and a negative GC-skew. Except for trnS1, for which we did not observe the DHU arm, all other tRNAs showed the cloverleaf secondary structure in the three species. In addition, the mitogenomes showed minor differences in start and stop codons, and in all PCGs, codons ending in adenine were more common compared to those ending in guanine. We found that PCGs of the three species use multiple codons to encode each amino acid, following the previously documented pattern. Furthermore, all PCGs are under purifying selection, with atp8 experiencing the most relaxed purifying selection. Considering the phylogenetic reconstruction, F. horrens was recovered as sister to Noctilio leporinus, L. aurita and Tonatia bidens shared a node within Phyllostomidae, and N. macrourus appeared as sister to Molossidae and Vespertilionidae.