Insight into phylogeny of Alburnus (Cypriniformes: Leuciscidae) with zooming in on Peri-Adriatic region

Abstract To date, the phylogeny of Alburnus , one of the most speciose western Palearctic freshwater fish genera, remains unresolved and its monophyly questioned. Here, we present a taxon-dense phylogeny of the genus and related genera, based on mitochondrial and nuclear DNA sequence data. A special focus is put on relationships between the Peri-Adriatic species. Our analyses confirmed the paraphyly of Alburnus with the retrieval of Leucaspius delineatus , Anaecypris punica and Anaecypris hispanica as three separate clades within it. This finding challenges the current taxonomic framework of the genus and highlights the need for a re-evaluation of its classification. The remaining three well-supported clades are currently assigned to Alburnus : Clade I from Levant and the Tigris and Euphrates basins, Clade V with shemayas and Clade VI comprising all remaining species: from Europe, Ponto-Caspian and Aral regions and Anatolia. Most relationships within Clade V and VI were not resolved likely due to rapid diversification in the late Pliocene and Pleistocene. Monophyly of the Peri-Adriatic group, suggested in previous works, was not confirmed. Moreover, Alburnus arborella did not form a monophyletic lineage and displayed extraordinary diversity both in its native and introduced range. Finally, new evidence for introductions of species were provided.