Hagfish

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Hagfish
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Class Myxini, Hagfish

• Members of the class Myxini have a partial
  cranium (skull), but no vertebrae. Their skeleton
  is made of cartilage, as is that of sharks.
• Hagfish lack jaws, and for this reason used
  to be classified with the lampreys in a group
  called the Agnatha ("no jaws") or the
  Cyclostomata ("round mouth").

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Names and size

• Common Name(s)Hagfish
• Scientific NameMyxine glutinosa
• Usual Sizeup to 45cms.

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Hagfish facts

• Breeding A hermaphrodite, which lays numerous,
  large eggs in a hard case. It is unlikely that
  these fish are self-fertilizing hermaphrodites
  and need a partner to breed.
• HabitatHagfish are found in all depth of water
  and lie buried in fine sands or silt when not
  feeding
• FoodMost fish, living or dead. Hagfish are the
  first fish to find their way to any dead animals
  which find their way to the seabed. They are
  parasitic on live fish, attaching themselves to
  the side and slowly eating their way through the
  fish. It has been known to find Cod with as many
  as 30 young Hagfish attached to them.

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Additional Notes

• Hagfish belong to the group of primitive, jawless
  fish which includes the marine and freshwater
  lampreys. They are considered a threat to
  commercial fish stocks of the North Sea because
  if the fish are not killed outright by the
  attacks, they usually succumb to later infections
  caused by the large wounds left by the Hagfish.

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Notes

• An unmistakable eel-like body that is
  uniformly pink in color. The mouth is a slit
  surrounded by fringe of short, fleshy barbels. A
  fleshy fin runs from the vent to the rear portion
  of the back, and a row pores runs along both
  sides from the head to the tail. A thick layer of
  glutinous slime (hence specific name) covers the
  whole body and can be sloughed in copious amounts
  when handled

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Slime ducts

• Hagfish - note the row of ducts located
  ventrally along the body for the exit of mucous
  from the numerous slime glands

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Deep sea livingHagfish Eptatretus(probably
deani, depth107-2743m, mainly 250-1200m).
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Lampreys
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Rattail
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Rattail or Grenadier fish
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Rattail or Grenadier fish

• Termed benthopelagic fish because they swim
  just above the bottom, these relatives of cod are
  the most common fish of bathyl and abyssal
  habitats. The deepest grenadier observed lives
  down to 6500m.Rattails have huge heads, large
  eyes, and long tapered tails. They have swim
  bladders--which may be used to make sound as well
  as to float--and cruise slowly above the bottom
  searching for live animals and carcasses to eat.
  The Russians have been catching these fish for
  food for many years now, and their numbers are
  declining in their waters. For a recent article
  on such deep-sea fishing, see New Scientist, Nov.
  8, 1997.

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Skate egg case
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White Skate (ob)Bathyraja spinosissima
(1200-2100 m)
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Skates

• These soft-nosed cartilaginous fish are
  inhabitants of the continental slopes. Like the
  common skates of shallow waters, they are
  carnivores that rest on the bottom and swim with
  their "wings," and lay eggs in capsules (above)
  that look like a piece of algal detritus.
  Possibly the deepest-dwelling skate is Rajella
  bigelowi from the North Atlantic (300-4100m).

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Urochordata

• Tunicates and Lancelets

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