Abstract
The diagnostic features of the Ponto-Caspian gobiid genus Knipowitschia Iljin, 1927 and related European genera are summarized with reference to the cephalic lateral-line system. The Adriatic Gobius panizzae Verga, 1841 is now shown to belong to Knipowitschia, and a second species, K. caucasica (Kawrajsky, in Berg, 1916), widespread in the Ponto-Caspian region, is recorded from the northern Adriatic (Gulf of Venice). The occurrence of these species in the Adriatic Sea is explained by Quaternary changes in union between the Mediterranean and Black Sea, with K. panizzae derived from Black Sea Knipowitschia stock emigrating via a temporary Riss/Würm interglacial confluence, and the K. caucasica of very recent origin through the existing postglacial connexion. A redescription of K. panizzae, based on syntypes and more recent material, is provided in an Appendix.