Banded kokopu

Banded kokopu are a stout-bodied fish, with a large head and mouth. The fish are strong, rounded and fleshy. Like other galaxiids, the dorsal and anal fins are positioned close to the tail fin, which is short and square. The caudal peduncle is short and deep, with thick fleshy flanges which join the tail fin. Adults are usually a dark, earthy brown or olive brown, with pale yellow vertical bands along the body. The belly is light coloured and unpatterned. Behind the operculum and above the pectoral fin is a silver or white mark, and sometimes a darker mark behind this. The bands either fade out top and bottom, or fork and crisscross the back of the fish. In small fish the bands are usually numerous and along the whole body, but in adults the bands become narrower and are often restricted to the rear third of the body. Although the bands change as the fish ages, the placement and shape of the bands are consistent enough to be used for individual identification over several years. Medium and juvenile giant kokopu can sometimes be mistaken for banded kokopu, as they can also develop vertical stripes. The easiest way to differentiate between the two species is that banded kokopu have a white or silver mark immediately behind the operculum, above the pectoral fin, and giant kokopu do not. Also, the markings of banded kokopu either fork and spread across the back of the fish, or fade out top and bottom, while the markings on giant kokopu never fork, and have a crisp edge all the way around. Juvenile shortjaw kokopu may also be mistaken for a very pale and poorly marked banded kokopu, but the small mouth of the shortjaw is diagnostic.