Heptranchias haswelli* Ogilby, 1897 Heptranchias pectorosus Garman, 1884 Heptranchias spilotus Lahille, 1913 Notidanus ferox Perez Canto, 1886 Notidanus indicus Agassiz, 1838 Notidanus medinae Philippi, 1902 Notidanus wolniczkyi Philippi, 1902 Notorynchus macdonaldi Whitley, 1931 Notorynchus maculatus Ayres, 1855 Notorhynchus borealis Gill, 1864 Notorhynchus ocellatus Devincenzi, 1920 Squalus cepedianus Péron, 1807 Squalus platycephalus Tenore, 1809 * ambiguous synonym The broadnose sevengill shark (Notorynchus cepedianus) is the only extant member of the genus Notorynchus, in the family Hexanchidae.

Because of this, it was listed along with the sharpnose sevengill shark (Heptranchias perlo) by Guinness World Records as having the most gill slits.

[2] It is similar to the sharpnose sevengill shark but the latter has a pointed snout and lacks spots on its dorsal surface.

[3][4] The sevengill species are also related to ancient sharks as fossils from the Jurassic Period (200 to 145 million years ago) also had seven gills.

The specific epithet cepedianus is derived from a variation of the name Lacepede, which refers to Bernard Germain de Lacépède, a French naturalist during the late 18th and early 19th century.

The common name "broadnose sevengill shark" refers to the seven gill slits the species possesses and the shape of its snout.

Common names from other languages include cação-bruxa (Portuguese), cañabota gata, gatita, tiburón de 7 gallas, tiburón pinto, and tollo fume (Spanish), ebisuzame and minami-ebisuzame (Japanese), gevlekte zevenkieuwshaai (Dutch), Kammzähner and Siebenkiemiger Pazifischer Kammzähner (German), koeihaai (Afrikaans), k'wet'thenéchte (Salish), platneus-sewekiefhaai (Afrikaans), platnez and requin malais (French), siedmioszpar plamisty (Polish), and tuatini (Maori).

These sharks are mainly benthic in nature, cruising along the sea floor and making an occasional foray to the surface.

[12] Individuals that live closer to the coast in South Africa tend to prefer more open areas with a sandy sea floor and sparse clumps of kelp.

[10] An opportunistic predator, the broadnose sevengill preys on a great variety of animals, and has been found at depths of 1,870 feet (570 meters), in offshore waters.

It will also feed on anything that fits in its mouth, such as shark egg cases, sea snails, crustaceans and any remains of rats, seabirds, and even deceased drowned humans.

It also found that, as Norfolk Bay does not have adequate shelter cover, this species may use group formation to avoid predation.

[23] After a 12-month gestation period, the female moves to a shallow bay or estuary to give birth between April and May[24] to a large litter of between 82 and 95 pups, measuring 40–45 cm (15.5–17.5 in).

[29] In 2004, John G Maisey of the American Museum of Natural History published a detailed analysis of the broadnose sevengill shark including imagery such as CT scans and morphology of its braincase.

[27] It is also threatened by water pollution and is hunted for its liveroil and hide which is considered good quality in places such as China.

[33] Its meat and fins are in demand in countries such as the US, Brazil, Spain, Germany, Netherlands and Israel, and is packaged for frozen food.

[34] The broadnose sevengill is also a source of vitamin A and utilized by South African sport anglers for winter tournaments, however, this shark is not easy to land despite being readily hooked.

[22] In Victoria, Australia, the Department of Environment and Primary Industries sets a one bag limit and must be whole or in carcass form.