![]() ![]() In 1865, American ichthyologist Theodore Nicholas Gill coined the new genus Isistius for this species, after Isis, the Egyptian goddess of light. l'Uranie et la Physicienne, Louis de Freycinet's 13 volume report on the voyage. In 1824, their account was published as part of Voyage autour du monde.sur les corvettes de S.M. The International Union for Conservation of Nature has listed the cookiecutter shark under least concern, as it is widely distributed, has no commercial value, and is not particularly susceptible to fisheries.įrench naturalists Jean René Constant Quoy and Joseph Paul Gaimard originally described the cookiecutter shark during the 1817–1820 exploratory voyage of the corvette Uranie under Louis de Freycinet, giving it the name Scymnus brasiliensis because the type specimen was caught off Brazil. Nevertheless, this diminutive shark is not regarded as dangerous to humans. Though rarely encountered because of its oceanic habitat, a handful of documented attacks on humans were apparently caused by cookiecutter sharks. ![]() This species has been known to travel in schools. ![]() When a would-be predator approaches the lure, the shark attaches itself using its suctorial lips and specialized pharynx and neatly excises a chunk of the flesh using its bandsaw-like set of lower teeth. Its dark collar seems to mimic the silhouette of a small fish, while the rest of its body blends into the downwelling light via its ventral photophores. Cookiecutter sharks have adaptations for hovering in the water column and likely rely on stealth and subterfuge to capture more active prey. It also consumes whole smaller prey such as squid. Marks made by cookiecutter sharks have been found on a wide variety of marine mammals and fishes, as well as on submarines, undersea cables, and even human bodies. The name "cookiecutter shark" refers to its feeding habit of gouging round plugs, as if cut out with a cookie cutter, out of larger animals. It is dark brown, with light-emitting photophores covering its underside except for a dark "collar" around its throat and gill slits. Reaching only 42–56 cm (16.5–22 in) in length, the cookiecutter shark has a long, cylindrical body with a short, blunt snout, large eyes, two tiny spineless dorsal fins, and a large caudal fin. It migrates vertically up to 3 km (1.9 mi) every day, approaching the surface at dusk and descending with the dawn. This shark occurs in warm, oceanic waters worldwide, particularly near islands, and has been recorded as deep as 3.7 km (2.3 mi). The cookiecutter shark ( Isistius brasiliensis), also called the cigar shark, is a species of small squaliform shark in the family Dalatiidae. Scymnus brasiliensis Quoy & Gaimard, 1824 ![]()
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