Geographical isolation and restricted gene flow drive speciation of Aegla singularis (Decapoda: Anomura: Aeglidae) in southern South America

EVA CAROLINA RUEDA; PABLO COLLINS; LORETÁN, GISELA; MARCOS PÉREZ-LOSADA; JUAN MANUEL CABRERA; FEDERICO GIRI

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020 vol. 129 p. 177 - 189

0024-4066

Geographical isolation is a key element in allopatric speciation. If gene flow is interrupted for long enough bygeographical barriers, populations can evolve independently and eventually form distinct species. Aegla singularisprovides an ideal model to study this process due to the characteristics of the geographical area that it occupies and itslimited dispersal ability. Aegla singularis inhabits streams of the Uruguay and Paraná River basins in the Neotropicalregion of South America. The basins are separated by the Sierra Central Mountains. Here we studied the speciationof A. singularis resulting from geographical isolation by using molecular and morphometric data. Individuals ofA. singularis were analysed using geometric morphometrics and genetic data (COII and EFα1). We found significantdifferences in shape and genetics between A. singularis populations from the two basins. These differences suggestongoing divergence due to restricted gene flow caused by the geographical barrier of the Sierra Central Mountains,indicating that the populations of the Parana and Uruguay River slopes are undergoing divergence.