Abstract
Background: Leuciscinae is a subfamily belonging to the Cyprinidae fish family that is widely distributed in
Circum-Mediterranean region. Many efforts have been carried out to deciphering the evolutionary history of this
group. Thus, different biogeographical scenarios have tried to explain the colonization of Europe and
Mediterranean area by cyprinids, such as the “north dispersal” or the “Lago Mare dispersal” models. Most recently,
Pleistocene glaciations influenced the distribution of leuciscins, especially in North and Central Europe. Weighing
up these biogeographical scenarios, this paper constitutes not only the first attempt at deciphering the
mitochondrial and nuclear relationships of Mediterranean leuciscins but also a test of biogeographical hypotheses
that could have determined the current distribution of Circum-Mediterranean leuciscins.
Results: A total of 4439 characters (mitochondrial + nuclear) from 321 individuals of 176 leuciscine species
rendered a well-supported phylogeny, showing fourteen main lineages. Analyses of independent mitochondrial
and nuclear markers supported the same main lineages, but basal relationships were not concordant. Moreover,
some incongruence was found among independent mitochondrial and nuclear phylogenies. The monophyly of
some poorly known genera such as Pseudophoxinus and Petroleuciscus was rejected. Representatives of both
genera belong to different evolutionary lineages. Timing of cladogenetic events among the main leuciscine
lineages was gained using mitochondrial and all genes data set.
Conclusions: Adaptations to a predatory lifestyle or miniaturization have superimposed the morphology of some
species. These species have been separated into different genera, which are not supported by a phylogenetic
framework. Such is the case of the genera Pseudophoxinus and Petroleuciscus, which real taxonomy is not well
known. The diversification of leuciscine lineages has been determined by intense vicariant events following the
paleoclimatological and hydrogeological history of Mediterranean region. We propose different colonization
models of Mediterranean region during the early Oligocene. Later vicariance events promoted Leuciscinae
diversification during Oligocene and Miocene periods. Our data corroborate the presence of leuciscins in North
Africa before the Messinian salinity crisis. Indeed, Messinian period appears as a stage of gradually Leuciscinae
diversification. The rise of humidity at the beginning of the Pliocene promoted the colonization and posterior
isolation of newly established freshwater populations. Finally, Pleistocene glaciations determined the current
European distribution of some leuciscine species.