Black hagfish

Black hagfish
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Myxini
Order: Myxiniformes
Family: Myxinidae
Genus: Eptatretus
Species: E. deani
Binomial name
Eptatretus deani
(Evermann & Goldsborough, 1907)[1]
Synonyms
  • Polistotrema curtissjamesi Townsend & Nichols, 1925
  • Polistotrema deani Evermann & Goldsborough, 1907

Eptatretus deani, known as the black hagfish, is a species of hagfish.

Common to other species of hagfish, their unusual feeding habits and slime-producing capabilities have led members of the scientific and popular media to dub the hagfish as the most "disgusting" of all sea creatures.[2][3][4] Although hagfish are sometimes called "slime eels", they are not eels at all.[5]

Description

This eel-like species is uniform black, or dark brown. It can also appear prune-colored, and often piebald with light spots. The edges of the ventral finfolds and caudal may have a light colour.[6] Unlike the Pacific hagfish, the black hagfish does not have a white ring around their gill pores.[6] It has no true fins, but instead, one dorsal finfold, far back on its body. It has a moderately broad and round caudal, with ray-like markings. The ventral finfold is very low. The black hagfish is scaleless, and ranges from 30 - 89 cm (35 in),[7] with an average maximum overall length of 64 cm (25 in).[8]

This species has four hearts, and 10 to 14 pairs of gill pores, It has rudimentary eyes. Although they have poor vision, they have a highly developed sense of smell and touch. The head of this species has one, large nostril, and eight barbels that surround the mouth and nostril. They have two parallel rows of horny teeth.

Distribution

Black hagfish are strictly marine, and are found in the Eastern Pacific from southeastern Alaska to central Baja California, and Mexico. These Bathydemersal fish live in the mesopelagic to abyssal Pacific ocean, near the ocean floor between depths of 103 and 2743 metres.[6][7][8]

Behaviour

Like other hagfish, this species attacks hook-caught or trap-caught fish. They burrow into the prey's body to consume the flesh and viscera within.[9] They also feed on carcases of fish that have died and sunk to the ocean floor.

Uses

In many parts of the world, including the US, hagfish skin is used for clothing, belts, or other accessories.[10] In the United States, the black hagfish has been trapped for commercial purposes. Trapping in Oregon began in October, 1988 in Newport. The hagfish are frozen whole, at sea, and then shipped to South Korea.[11]

Recent studies have shown, that hagfish slime has similar properties of spider silk, strong and light. If hagfish slime could be replicated in laboratories it could replace artificial materials, like nylon, in women's stockings and workout pants. This would ultimately be better for the environment since nylon is produced from petroleum,and hagfish slime threads could be implanted into bacterium and grown with no harm to the environment. [12]

Egg characteristics

Mature females usually contain up to 42 eggs. The average is 4 eggs over 5 mm long. Mature black hagfish females often contain various sized groups of eggs -- sometimes having three distinct size groups. Contained in a typical gonad might be: one group with eggs from 19 - 22 mm, another group with eggs ranging from 1 - 4 mm, and a third group of eggs less than 1mm long. Ovaries often contain over 200 eggs, each less than 1 mm.[11]

Development of eggs in mature female hagfish gonads

Gonad stages

The image to the right shows the various stages of egg development:

Slime

Black hagfish produce copious amounts of slime as a defense mechanism. Deep-sea diving equipment is known to have been fouled by large amounts of hagfish slime near the bottom of the ocean, extruded by the eel-like fish when they are alarmed. The slime comprises mature thread cells, up to 10 cm (4 in) long that are coiled and thread-like.[13]

See also

Further reading

References

  1. ↑ "ITIS Standard Report Page: Eptatretus deani". Itis.gov. 2003-03-17. Retrieved 2010-07-30.
  2. ↑ "Friends of Oceanography Public Lecture Series - Explores the Strange, Wondrous, and Disgusting Hagfish". University of Rhode Island. 2002-03-25. Retrieved 2008-02-19.
  3. ↑ "Slimy, disgusting and useful". Norwegian University of Science and Technology. Retrieved 2008-02-19.
  4. ↑ Frank, Tammy (2004-08-09). "Disgusting Hagfish and Magnificent Sharks". NOAA Ocean Explorer. Retrieved 2008-02-19.
  5. ↑ Sea and Sky: Atlantic Hagfish
  6. 1 2 3 http://fishbase.org/Summary/SpeciesSummary.php?id=2511
  7. 1 2 "Species Information". Seaaroundus.org. Retrieved 2010-07-30.
  8. 1 2 Stephen Sempier (2003-03-29). "Black Hagfish". Hmsc.oregonstate.edu. Retrieved 2010-07-30.
  9. ↑ "Pacific hagfish, Eptatretus stouti, and black hagfish, E. deani: the Oregon Fishery and Port sampling observations, 1988-92. | North America > United States from". AllBusiness.com. Retrieved 2010-07-30.
  10. ↑ Barss, William (1993). "Pacific hagfish, Eptatretus stouti, and black hagfish, E. deani: the Oregon Fishery and Port sampling observations, 1988-92". Marine Fisheries Review (Fall, 1993). Retrieved April 21, 2010.
  11. 1 2 Pacific Hagfish, Eptatretus stouti, and Black Hagfish, E. deani: The Oregon Fishery and Port Sampling Observations, 1988-92
  12. ↑ Kaufman, R. (2014, April 22). Hagfish slime could be eco-friendly fabric. Retrieved November 27, 2014, from http://voices.nationalgeographic.com/2014/04/22/hagfish-slime-animals-science-weird-fish/
  13. ↑ Acta zoologica. Internationell tidskrift for zoologi, Volumes 62-63, p.137

External links

This article is issued from Wikipedia - version of the 11/19/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.