Gudgeon (Gobio), a genus of small, carp-like (Cyprinoid) fishes common in the fresh waters of Europe. The dorsal fin is short, without a spine; the mouth is directed downwards, and has little barbules at the angles; the scales are of moderate size; and there are two rows of hooked pharyngeal teeth. The common gudgeon (G. fluviatilis), which abounds in many English rivers, especially in those that run over gravel, is a small fish rarely exceed- ing 8 inches in length, with upper parts olive-brown, spotted with black, and the under parts white. The gudgeons swim in shoals, and, like the barbel, feed on worms, molluscs, and other small animals.
Angling for gudgeon requires no art, so readily are the fish lured. Though small, the fish are esteemed for the table. Besides the British gudgeon, which is widely distributed on the Continent, there is only another species (G. uranoscopus), also European, but apparently restricted to the river-basins of the Danube and Dniester; allied genera occur in the East.