Salenthydrobia gen. nov. (Rissooidea: Hydrobiidae): a potential relict of the Messinian salinity crisis |
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Authors: | THOMAS WILKE |
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Affiliation: | The George Washington University Medical Center, Department of Microbiology and Tropical Medicine, 2300 Eye Street, N.W., Washington, DC 20037, USA and J.W. Goethe-Universität Frankfurt am Main, Abteilung Ökologie &Evolution, BioCampus, Siesmayerstraße, D-60054 Frankfurt am Main, Germany |
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Abstract: | The Messinian salinity crisis (MSC) occurred synchronously throughout the Mediterranean basin about 5.96 ± 0.02 Mya and represents one of the most dramatic oceanic changes since the early Miocene. It is thought that the concomitant environmental changes brought about isolation of faunas and the development of endemism. As part of the search for possible speciation events triggered by the MSC, the author studied 38 populations of hydrobiine snails from the Mediterranean and Black Sea, including three populations from the Salentina Peninsula, Italy. Partial sequences (COI, 16S) and anatomical data were used to test the taxonomic and phylogenetic status of the peninsular populations. A maximum likelihood analysis of 11 hydrobiine taxa revealed five clades and lineages, four of which corresponded to previously recognized genera: Adriohydrobia , Hydrobia , Peringia , Ventrosia . The fifth clade was formed by haplotypes of the peninsular populations, which are characterized by distinct male and female reproductive systems. Based on molecular and anatomical data, these populations are considered to represent a new species, Salenthydrobia ferrerii , belonging to a new genus, Salenthydrobia . Ecological and biogeographical data for S. ferrerii strongly support a correlation between its origin and the MSC. Based on an island age of 5.33 Myr and a population divergence of 0.0973 ± 0.0114, the COI molecular clock rate for the Salenthydrobia and Peringia clades would be 1.83 ± 0.21% population divergence per Myr. The genetic diversity of S. ferrerii , its phylogenetic relationships, and the validity of the proposed local molecular clock rate are discussed. |
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Keywords: | COI mtDNA 16S rRNA Hydrobiinae phylogeography |
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