The Gudgeon (Gobio gobio) is a freshwater fish in the Cyprinidae family. It is a cyprinid. 

The Gudgeon has a long, slender body with a flat, wide head. It is usually greenish-brown with silvery sides. It has a row of 6-12 faint black-grey blotches running lengthwise on the side of its body. Its underbelly is white. Its fins are greyish-white with a brownish tinge. The dorsal (back) fin is pale-brown with small, dark spots. It has a barbel at the corner of each side of its mouth. It has two rows of teeth.

It grows to about 9-13 centimetres (3-5 inches) long.

It is widespread in streams and lakes in Europe and Asia. It likes habitats with gravel or soft, sandy bottoms and shallow water.

The Gudgeon is benthic because it lives on the bottom of the river where it forages for food. It feeds on worms, aquatic insects, larvae, and snails. The Eurasian Otter and the Kingfisher like to eat the Gudgeon. 

It is diurnal, active during the day. It lives in groups called shoals. 

The female lays eggs that drift in the water until they fall to the bottom of the river. They hatch into larvae, called fingerlings. 

It lives for about five years.

Location of photograph: Aquarium de Paris-Cinéaqua, France

Photographer: Martina Nicolls

Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM