The New Zealand brill, Colistium guntheri, is an edible flatfish

Flatfish

The flatfish are an order of ray-finned fish, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through and around the head during development...

 of the family Pleuronectidae

Pleuronectidae

Righteye flounders are a family, Pleuronectidae, of flounders. They are called "righteye flounders" because most species lie on the sea bottom on their left side, with both eyes on the right side. The Paralichthyidae are the opposite, with their eyes on the left side.Their dorsal and anal fins are...

. It is a demersal fish native to shallow seas around New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

, at depths of between 27 metres (88.6 ft) and 49 metres (160.8 ft). It can grow to 91 centimetres (35.8 in) in length and can weigh up to 1.8 kilograms (4 lb).

Identification

The New Zealand brill is a righteyed flounder and so has both its eyes on the right-hand side of its body. Its upper surface is dark grey in colour, with its edges and fins almost black; the outer edge of each scale is black, which explains the longitudinal black lines that occur along the length of the body.