The Ringneck blenny (Parablennius pilicornis) is a species of combtooth blenny widespread in coastal waters of Eastern Atlantic from Spain and Portugal to Möwe Bay, Namibia, in the Mediterranean Sea from Morocco, Algeria, Spain. In the Southwest Atlantic it is found near Brazil and Patagonia, Argentina. Also in Western Indian Ocean from Natal to Knysna in South Africa. This species reaches a length of 12.7 centimetres (5.0 in) SL.