Alepisaurus ferox

Alepisaurus ferox, the long snouted lancetfish, longnose lancetfish, or cannibal fish, is a species of lancetfish found in the ocean depths down to 1,830 m (6,000 ft). This species grows to 215 cm (85 in) in total length and a weight of 9 kg (20 lb). They are sometimes taken as by-catch in tuna long-line fisheries, but are not a targeted species. It is often called the cannibal fish because numerous individuals have been caught after having devoured other lancetfish. It lives in deep-water oceans in the Western and Eastern Pacific from the Aleutian Islands to Chile and the Western Atlantic from the Gulf of Maine to the Gulf of Mexico, including the Caribbean Sea, and the Eastern Atlantic, Indian Ocean, Northwest Atlantic, and the China Sea. The dorsal fin of A. ferox has about three rays strongly exserted, beginning with the third or fourth ray. It is known to have a large mouth with two fangs. It is generally pale, iridescent, and dark around the dorsal fin; all of its fins are either dark brown or black. The fish are simultaneous hermaphrodites, meaning they have both male and female reproductive parts at the same time. As mentioned earlier, A. ferox is referred to as the cannibal fish, due to its conspecific predation habits. A study conducted by Romanov, Ménard, Zamorov, and Potier (2008) found that the extent of cannibalism depended on the availability of non-conspecific prey. In abundant waters, A. perox will primarily hunt crustaceans, and in waters with fewer interspecific prey, conspecific predation will increase; the extent to which this behavior increases is dependent on the availability of other prey.