Cryptic diversity among populations of Aegla Leach, 1820 (Decapoda: Anomura: Aeglidae) from Tibagi River basin, Paraná state, Brazil, with descriptions of three new species

Abstract

ABSTRACT Freshwater crustaceans of the genus Aegla are endemic to southern South America. In Brazil, the greatest diversity of aeglid species occurs in river basins in the Rio Grande do Sul state. Nevertheless, recent studies have shown that the potential for discovering new species of Aegla in the Paraná state is huge. In recent years, for example, seven new species have been described for the state of Paraná. Furthermore, there is a need to solve problems related to cryptic species and refine taxonomic information about the group. Here we expand our current knowledge of the freshwater biodiversity of Aegla in the region by describing three new species. Aegla nanopedis sp. nov., Aegla abrupta sp. nov., and Aegla santosi sp. nov. were discriminated based on morphological and molecular evidence. Particular morphological characters of the carapace, chelipeds, epimeron and uropods distinguished the new taxa. Molecular results also support the separation of the new species from the closely related species A. jacutinga, A. castro and A. lata. The new species have limited distribution and are categorised as endangered (Aegla nanopedis sp. nov.) and vulnerable (Aegla abrupta sp. nov. and Aegla santosi sp. nov.) according to International Union for Conservation of Nature Red List Categories and Criteria.