An ancient and unique lineage of primitive eel-like marine fishes that mostly inhabit deeper temperate seas.
Hagfishes are renowned for their slime-producing abilities, and lack true jaws, and have degenerate eyes and many gill openings. They also have a single semicircular canal, and a single olfactory canal. They also lack vertebral centra, and rely only a notochord to support the body.
They play an important role in recycling organic matter and other nutrients in the ecosystems they inhabit. Hagfishes are scavengers and burrow into dead or dying fishes, invertebrates and marine mammals to feed on their insides. They also prey on small fishes and invertebrates.
Hagfishes are captured for food and their skins which are manufactured into leather. In parts of the world, hagfish populations are threatened by over-fishing.
Hagfishes have an evolutionary history dating back 300 M yrs. They share a joint ancestor with the entire vertebrate lineage. The class contains a single order and family with about 80 described species.
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