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griseus) click here.
Broadnose Sevengill Shark (Notorynchus cepedianus)
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Taxonomic name: Notorynchus cepedianus
Other Common Names: Seven-gilled Sahrk, Broad-snout Shark, Tasmanian Tiger Shark, Cowshark, Ground Shark.
The Broadnose Sevengill Shark has a wide international
distribution, primarily in temperate zones in both hemispheres and all oceans. It has a mouth that appears to caught in a tight-lipped grin with a narrow gap, as if permanently pursed in a whistle, that allows a free flow of water into the mouth and through the gills. Its one dorsal fin is
set well back on the body, near the elongated tail. The torso is slender but becoming bulky with large adults. The seven gill slits are distinctive but do not extend too far onto the throat region.
The teeth of the lower jaw resemble a hand saw, with a series of jagged
sloping points or cusps on a long base, rising in size at the end closest to the foremost point of the jaw. The upper teeth have similar rear-pointing
spikes but on a shorter base and with only two cusps, perfect for holding
large or small prey. The whole array is ideal for slicing apart both large
quarry, such as dolphins and sharks, as well as holding smaller animals
like crabs and squid.
The body is a grey to brownish with small black and white spots scattered along the back and flanks. The belly is white. Eyes are not as large as some of the deep water relatives of this species as it is often found in very shallow water or on the surface down to about 150 meters on the continental shelf. The caudal fin is long and flexible with the dorsal fin set very close to the tail above the forward margin of the anal fin. The pectoral fins are broad and short.
Offspring are born at 40-45 cm with distinct spots and at times a dark edge to the caudal fin and a white or clear edge to the other fins. Maximum size is at least 3 meters.
This shark will readily come into baits, at times targeted by sports and commercial fishers. Despite their smiling rictus they can be aggressive to divers if there is bait in the water. They tend to be more active and aggressive at dawn and dusk, hunting actively at night. They are indiscriminate feeders, happy to take both live prey, such as fish, other sharks, squid, seals, and carrion. They are solitary scavengers and hunters but will happily feed as a group if the situation dictates that. While they can put on a burst of speed they are generally a slow moving animal, preferring to use stealth and darkness to catch their prey. We have the world's largest and finest collection of this species in our database including adults and juveniles.