Evolutionary history of the Balkan endemic genus <i>Delminichthy</i><i>s</i> (Teleostei, Leuciscidae) with an emphasis on the population structure of Southern Dalmatian minnow

<p dir="ltr">The genus <i>Delminichthys</i> consists of allopatric species restricted to ephemeral watercourses in the karst fields of the left-bank (<i>D. ghetaldii</i>) and the right-bank (<i>D. adspersus</i> and <i>D. jadovensis</i>) Neretva River basin as well as in the Una River drainage (<i>D. krbavensis</i>). The first aim addressed questions of interspecies variation and phylogenetic relationships among <i>Delminichthys </i>based on time-calibrated analysis of <i>cyt </i>b mtDNA (cytochrome b) and <i>COI </i>mtDNA (cytochrome c subunit I) mitochondrial DNA genes. Species-specific haplogroups supported two mtDNA genes as suitable barcoding markers, while we additionally proposed character-based and genetic distance threshold-based delimitation of species. We confirmed that the Pliocene and Pleistocene refugium for freshwater species was the Neretva basin, promoting the diversification of the genus <i>Delminichthys. </i>Our second aim was to test the population structure of <i>D. ghetaldii</i> (Southern Dalmatian minnow) by performing an integrative study using molecular mtDNA data, linear and geometric morphometric data. We consider that the spatial aspects of the population genealogical structure of <i>D. ghetaldii </i>mirror the Pleistocene paleodrainages. The differentiated <i>COI </i>mtDNA clusters corresponding to the populations from Fatničko Polje+Dabarsko Polje and Ljubomirsko Polje+Konavosko Polje represent geographically discrete genetic entities, which should be addressed through conservation management.</p>