Hexanchiformes

Chlamydoselachidae (frilled shark)

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Hexanchidae (cow sharks)

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Hexanchiformes is the order consisting of the most primitive types of sharks, and numbering just five extant species.

Related Topics:
Order - Shark

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Hexanchiform sharks have only one dorsal fin, either six or seven gill slits, and no nictitating membrane in the eyes.

Related Topics:
Dorsal fin - Gill slit - Nictitating membrane

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The frilled shark, Chlamydoselachus anguineus, is very different from the cow sharks, and it has been proposed that it be moved to its own order Chlamydoselachiformes.

Related Topics:
Frilled shark - Cow shark - Chlamydoselachiformes

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