Putting European lampreys into perspective: A global-scale multilocus phylogeny with a proposal for a generic structure of the Petromyzontidae

Previous studies on the phylogenetic relationships between lamprey species relied either on a low number of morphological characters related to the feeding apparatus, or on a low number of molecular mitochondrial DNA markers. Here, we apply a multilocus approach to assess the phylogenetic relationships of northern hemisphere lampreys, with a special emphasis on the 17 European species. The study comprises two mitochondrial (cytochrome c oxidase subunit 1 gene-DNA barcodes, and cytochrome b gene) and two nuclear (internal transcribed spacers I and II) markers to investigate species' phylogenetic affinities. The phylogeny obtained with mitochondrial markers revealed a clear and highly supported separation of all northern hemisphere lampreys. Among those, our multilocus results show several polyphyletic genera, stressing the need for a taxonomic revision in a near future. Lampetra morii (Berg, 1931) from East Asia, often included in Eudontomyzon, is placed in the genus Lethenteron. Lampetra richardsoni Vladykov & Follett, 1965 and Entosphenus hubbsi (Vladykov & Kott, 1976) should be placed in a new genus, as well as the southern populations of Lethenteron camtschaticum (Tilesius, 1811) and Lethenteron reissneri (Dybowski, 1869). Considering European species, our results argue for a taxonomic revision of Eudontomyzon, with emphasis on Eudontomyzon vladykovi Oliva & Zanandrea, 1959.