Phylogenomic and biogeographic study of aeglid crustaceans (Decapoda: Anomura) from Atlantic Forest Basins, Brazil: patterns and processes associated with dispersal and diversification

• Grant number: 25/01018-8
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: May 01, 2025
• End date: January 31, 2028
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: Fernando Luis Medina Mantelatto
• Grantee: Lucas Oliveira Rogeri
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 18/13685-5 - Integrative analysis of the Brazilian fauna of decapod crustaceans: taxonomy, phylogenetic systematics, spermiotaxonomy, morphology of post-embryonic development, ecology and conservation, AP.BTA.TEM

Abstract

The decapod crustacean taxon Aegla Leach, 1820 corresponds to the only extant genus of the family Aeglidae Dana, 1852, endemic to South America and whose life cycle occurs exclusively in freshwater environments. In recent years, many species of Aegla have been described after the exploration of areas that until then had been little studied. This fact raises the possibility that other areas, which have never been the object of a systematic study regarding aeglids, may contain a diversity that is still unknown, as is the case of several basins that drain the Atlantic Rainforest biome. Furthermore, the existence of vast unexplored areas hinders the interpretation of the phylogenetic relationships within the taxon and the comprehension of the biogeographic history that marked the evolution of the group. Considering this scenario, the project proposes the exploration of three regions of the Atlantic Rainforest that have been little explored in terms of the taxon Aegla, the Rio Grande, Rio Tietê and Rio Paraíba do Sul Basins, through exploratory field expeditions and subsequent morphological and genetic evaluation of the material in the laboratory. Based on the results from the field expeditions, the analysis of material deposited in museums, the data generated, and the information available in the literature, this project intends to investigate the phylogenetic relationships between the collected Aegla species and others already described for the Atlantic Rainforest, aiming to understand the evolutionary history that permeates the diversification of the group in the biome. The project also aims to work the data in a biogeographic perspective in order to understand which biogeographic and geological events shaped the process of dispersal and diversification of the taxon Aegla throughout the Atlantic Rainforest, which constitutes an unprecedented aspect for the theme. Morphology will be studied by evaluating the characters of the specimens under a stereomicroscope, comparing the observed data with the available literature on the taxon, and will be the basis for describing possible new species that may be recognized. Genetic data will be generated by Sanger sequencing and next-generation sequencing. Sanger sequencing will be used to generate sequences of new species that may be recognized and described by the project, serving as DNA barcoding. Next-generation sequencing data will be used to build a phylogenetic hypothesis that includes species from the different river basins that drain the Atlantic Rainforest, and in the biogeographic analysis of the data to be conducted in R using the BioGeoBEARS package that integrates phylogenomic and occurrence data.