Hagfish

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Hagfish
Pacific hagfish resting on bottom
280 m depth off Oregon coast
Scientific classification
Kingdom: Animalia
Phylum: Chordata
(unranked): Craniata
Class: Myxini
Order: Myxiniformes
Family: Myxinidae
Genera

Eptatretus
Myxine
Nemamyxine
Neomyxine
Notomyxine
Paramyxine
Quadratus

Hagfish are craniata in the class Agnatha or Myxini, also known as Hyperotreti. Even though fish are supposed to have backbones, hagfish do not. Because of this, many researchers think Myxini should not be in the subphylum Vertebrata.[1] Their skeleton is made up of its skull, which is made out of cartilage. However, because of its fins and gills, they are called fish. They are marine, meaning they live in the sea.

Description[change | change source]

Hagfish are usually about half a meter (18 in) long. They have long, eel-like bodies. Hagfish's eyes are small and not very useful, because the hagfish uses mostly its senses of smell and touch to find food. The whiskers near the hagfish's mouth are called barbels, and are used for touching. They have four hearts, two brains, and no backbone.[2][3] A fish which looks like the hagfish is the lamprey.

Feeding[change | change source]

Hagfish eat invertebrates (animals such as worms) and are also scavengers, eating fish which are dead or dying. Hagfish have four sets of teeth on their tongue to bite pieces of flesh from its prey. They use these tongue teeth to eat. The teeth pinch together to lock onto its food, helping it tear into dead and dying fish which have sunk to the bottom of the sea, where it lives. Often, a hagfish digs into the dead fish that it is eating, removing the insides of the dead fish. [4]

Usually, people only see hagfish when nets that sweep the sea floor are pulled up. Every fish, even the dead ones at the bottom of the sea, are brought up into the boat by the net. In some of those dead fish, hagfish are found eating. The smelly fish are dumped onto the deck of ships with the hagfish poking out from their bodies.

Slime[change | change source]

When hagfish are afraid, they make slime. This slime comes out of the sides of the hagfish's body. They are able to make enough slime to completely fill a two-gallon bucket. The reason such a small fish can make so much slime is because the slime comes out in strings that quickly swell up much bigger when they are in the water.Their unusual way of eating and their slime has made many people call the hagfish the most "disgusting" of all sea creatures.[5][6][7] Although hagfish are sometimes called "slime eels," they are not eels at all.[8]

Kkomjangeo bokkeum (꼼장어 볶음), Korean stir-fried fish dish made with the hagfish Eptatretus burgeri.

Uses of Hagfish[change | change source]

Food[change | change source]

Hagfish are usually not eaten by humans in most countries. However, meat from the inshore hagfish (a type of hagfish known as kkomjangeo (꼼장어) or meokjango (먹장어) in Korean and Nuta-unagi in Japanese) is a popular food in Korea. [9]

A bag made from eel skin.

Material[change | change source]

Hagfish skin is used to make leather for wallets and belts. When this leather is sold, it is called "eel skin". [10]

Slime[change | change source]

Scientists are studying hagfish slime to see if they can use it to make things. The strings of protein in hagfish slime are thin and strong, so they are a useful material. Because it is not made from oil, hagfish slime would be more environmentally friendly than the plastics that we use now. [11]

References[change | change source]

  1. Neil A. Campbell and J. B. Reece 2005. Biology 7th ed, Benjamin Cummings, San Francisco CA.
  2. Aird WC (2007) Endothelial biomedicine p. 67. Cambridge University Press. ISBN 9780521853767
  3. Scholasticus K. "Hagfish Anatomy". Buzzle.com. http://www.buzzle.com/articles/hagfish-anatomy.html. Retrieved 10 March 2010.
  4. "Modern Jawless Fish: Hagfish and Lampreys" The Natural History Collections of the University of Edinburgh. 2006. Retrieved 2014-3-9.
  5. "Friends of Oceanography Public Lecture Series - Explores the strange, wondrous, and disgusting hagfish". University of Rhode Island. 2002-03-25. http://www.uri.edu/news/releases/html/02-0325-01.html. Retrieved 2008-02-19.
  6. "Slimy, disgusting and useful". Norwegian University of Science and Technology. http://www.ntnu.no/gemini/2003-06e/26-27.htm. Retrieved 2008-02-19.
  7. Frank, Tammy (2004-08-09). "Disgusting hagfish and magnificent sharks". NOAA Ocean Explorer. http://oceanexplorer.noaa.gov/explorations/04deepscope/logs/aug9/aug9.html. Retrieved 2008-02-19.
  8. Sea and Sky: Atlantic Hagfish
  9. "Eptatretus stoutii" Animal Diversity Web, University of Michigan Museum of Zoology. 2006. Retrieved 2014-3-9.
  10. "Eel for Real" snopes.com. 2007-7-21. Retrieved 2014-3-9.
  11. "Hagfish Slime Makes Super-Clothes" Eric Niiler, Discovery News. 2012-12-3. Retrieved 2014-3-9.

Other websites[change | change source]