Phylogeny, systematics and biogeography of the European sand gobies (Gobiiformes: Gobionellidae)

The sand gobies are a group of 30 species in five genera (Knipowitschia, Pomatoschistus, Economidichthys, Ninnigobius and Orsinigobius) native to the seas and fresh waters of Europe and the Ponto-Caspian region. We construct a phylogeny incorporating new DNA sequence data (mitochondrial COI gene) for species in Greece and the Adriatic (Venetian Lagoon) with existing sequences sampled from throughout European waters. Our comprehensive analysis confirms the distinctness of Orsinigobius and Ninnigobius, supports that Gobiusculus is part of Pomatoschistus and supports the monophyly of Economidichthys and Knipowitschia. We then calibrate the phylogeny using fossils, interpret the phylogenetic biogeography of sand gobies throughout Europe and the Mediterranean and estimate the historical divergence patterns in the group. We infer the origin of the sand goby clade at 33.0 Mya, near the Eocene–Oligocene boundary, and show that radiations among marine Pomatoschistus clades in the Miocene are correlated with the closure of the Tethys seaway. Younger freshwater clades of Ninnigobius, Orsinigobius and subclades of Knipowitschia diversified in the late Miocene and early Pliocene, centred in the Adriatic region and concordant with the Lago Mare phase of the Messinian salinity crisis. Economidichthys is the exception to this pattern; it inhabits freshwater but originated and diversified during the mid-Miocene.