Macrourus

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Macrourus is a small genus of rattail fish in the family Macrouridae. These benthopelagic fish live on the upper to middle continental slopes in cold temperate and polar waters of the North and South Atlantic and the Southern Ocean. They occur from about 200 meters deep to more than 3,000 meters, usually in water temperatures of 1–4 °C, though one species, M. whitsoni, has been found at slightly below 0 °C. They are important food fishes in the North Atlantic and off Patagonia. They are often bycatch in the northeastern Atlantic but are sometimes landed; catches between 1990 and 2015 ranged from almost nothing to about 4,000 tonnes.

Appearance and biology: Macrourus fish have large broad heads that are more than four times as deep as they are long, with a snout that can be rounded or bluntly pointed and a distinctive modified spiny scale at the tip. A strong ridge runs under the eye to the preopercle ending in a sharp point. Eyes are about one-third the head length. Teeth are small and arranged in bands on both jaws, with the lower jaw having 3–4 teeth across the center, narrowing to one row toward the lips. The dorsal fin has serrated spiny rays; the pelvic fin usually has 8–9 rays. The anus opens at the base of the anal fin, and there are no photophores. They can grow to about 100 cm (roughly 39 inches) long.

Taxonomy: There is ongoing confusion about the genus’ type species. Bloch named Macrourus rupestris as the type, but that name is a synonym of Coryphaenoides rupestris. In 1917, Jordan proposed Macrourus berglax as the type, but the issue remains unclear, with Sundevall noting that M. berglax may be Coryphaenoides rupestris and suggesting M. berglax should be called M. fabricii. The matter has not been fully resolved by the ICZN. There are five recognized species in the Macrourus genus today.