A new species of the gobiid genus Gobius (Gobiidae, Perciformes), Gobius incognitus sp. nov. is described from the Mediterranean Sea, and its most morphologically similar species Gobius bucchichi is redescribed. The new species is distinguished from its congeners by: scales in lateral series 51-59; predorsal scales 25-35; opercle scaled in adults with 10-16 scales present; pectoral fin with ray count 18-20 and free tips on upper rays well developed and on the first ray longer than two thirds of the entire ray length; pelvic disc complete and with well-developed anterior membrane without lateral lobes; anterior oculoscapular canal with pore α at rear of orbit; oculoscapular row x(1) not extending forwards to pore β; suborbital row d discontinuous with large gap below suborbital rows 3 and 4; eye diameter 1·08-1·32 in snout length; by pigment rows on cheek and pigmentation on pectoral-fin base.
Keywords: Adriatic Sea; Gobius incognitus sp. nov.; Gulf of Lyon; gobies; systematics.
© 2016 The Fisheries Society of the British Isles.