Evidence of a cenozoic Betic-Kabilian connection based on freshwater fish phylogeography (Luciobarbus, Cyprinidae)

The phylogenetic relationships among 26 species of the subgenus Luciobarbus were examined through comparison of the complete sequence of the mitochond rial genes ATPase 6 and 8 and cytochrome b. The monophyletic condition of t he Luciobarbus subgenus was confirmed by several data treatment methods. Fi ndings indicate a closer relationship among species inhabiting Caucasian, C reek, and North African areas than between the latter and those of the Iber ian region. The isolation of these main clades is postulated to have occurr ed after the Messinian salinity crisis (5.5 MY ago) when the Iberian Penins ula broke away from the African continent. Based on a calibrated molecular clock proposed herein, the subsequent splitting of this subgenus correspond s to the isolation of the other three areas (Caucasian, Creek, and North Af rican) about 4.5 MY ago, which would have interrupted any possible gene flo w between lineages. However, the present data indicate that the North Afric an Kabilies Mountain area maintained its contact with the south Iberian Pen insula for a longer period. (C) 2001 Academic Press.