Phylogenetic relationships of Ponto‐Caspian gobies and their relationship to the Atlantic—Mediterranean Gobiinae

Abstract

A phylogenetic analysis for five Ponto‐Caspian goby species belonging to the two genera Neogobius and Proterorhinus assigned to the sub‐family Gobionellinae was conducted, with five Atlantic—Mediterranean species of sub‐family Gobiinae, genera Gobius and Zosterisessor, as outgroup taxa. One hundred and two characters (37 continuous cranial osteological, 50 continuous external morphological, five discrete external morphological, four karyological, two vertebral and four external discrete qualitative characters) were studied. Parsimony analysis revealed that the two zoogeographically distinct groups of goby species comprise distinct phyletic lineages that are sister groups. The relation of neogobiids to the sub‐family Gobiinae was reconsidered, due to the sharing of the same state for the diagnostic character. The recently proposed classification for the genera Proterorhinus and Zosterisessor was rejected. The status of several of the lower ranked taxa was also considered [e.g. Gobius bucchichi as a member of the genus Zosterisessor and the sub‐generic status of Neogobius (Neogobius) fluviatilis and Neogobius (Apollonia) melanostomus]. The paleohistorical data suggest that those lineages, which may both descend from pre‐Oligocene Indo‐Pacific ancestors, separated at least 12 million years ago, during the early Miocene, after the formation of the Paratethys Sea, and then evolved independently. The Tethyan gobiine species evolved in the marine environment of the Mediterranean Sea and the Atlantic Ocean. The Ponto‐Caspian (i.e. Paratethyan) gobies of the genera Neogobiusa and Proterorhinus diverged in the late Miocene or early Pliocene. They probably evolved in the freshwater refuge in the Daccian Basin of the Paratethys Sea (the recent Black Sea basin).