Eptatretus wisneri

Taxonomy

Assessment Information

Geographic Range

Population

Habitat and Ecology

Threats

Conservation Actions

Bibliography

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Taxonomy [top]

Kingdom	Phylum	Class	Order	Family
ANIMALIA	CHORDATA	MYXINI	MYXINIFORMES	MYXINIDAE

Scientific Name:	Eptatretus wisneri
Species Authority:	McMillan, 1999

Assessment Information [top]

Red List Category & Criteria:	Least Concern ver 3.1
Year Published:	2011
Date Assessed:	2009-11-11
Assessor/s:	Mincarone, M.M.
Reviewer/s:	Polidoro, B., Knapp, L. & Carpenter, K.E.
Justification: This species is known only by two museum specimens and is likely endemic to Galápagos Archipelago. It is likely a deepwater species, as specimens were recorded between 512 and 563 m. There are no known threats likely to affect this species, given its deep water habitat. It is also found entirely within the Galápagos Marine Protected Area. It is listed as Least Concern. However, more research is needed on this species population, biology, life history, and potential threats.

Geographic Range [top]

Range Description:	This species is found within the Galápagos Archipelago, west of Fernandina Island (McMillan 1999).
Countries:	Native: Ecuador (Galápagos)
FAO Marine Fishing Areas:	Native: Pacific – southeast
Range Map:	Click here to open the map viewer and explore range.

Population [top]

Population:	The population of this species is only known from two type specimens.
Population Trend:	Unknown

Habitat and Ecology [top]

Habitat and Ecology:	This species is found on the slope at depths from 512-563 m. The holotype is a 356 mm juvenile female with round eggs of less than 1 mm, with no ellipsoidal oocytes. The paratype is a 328 mm male with well-developed testes (McMillan 1999). The copulatory organ is absent in this species. The gonads of hagfishes are situated in the peritoneal cavity. The ovary is found in the anterior portion of the gonad, and the testis is found in the posterior part. The animal becomes female if the cranial part of the gonad develops or male if the caudal part undergoes differentiation. If none develops, then the animal becomes sterile. If both anterior and posterior parts develop, then the animal becomes a functional hermaphrodite. However, hermaphroditism being characterised as functional needs to be validated by more reproduction studies (Patzner 1998).
Systems:	Marine

Habitat and Ecology:

This species is found on the slope at depths from 512-563 m. The holotype is a 356 mm juvenile female with round eggs of less than 1 mm, with no ellipsoidal oocytes. The paratype is a 328 mm male with well-developed testes (McMillan 1999).

The copulatory organ is absent in this species. The gonads of hagfishes are situated in the peritoneal cavity. The ovary is found in the anterior portion of the gonad, and the testis is found in the posterior part. The animal becomes female if the cranial part of the gonad develops or male if the caudal part undergoes differentiation. If none develops, then the animal becomes sterile. If both anterior and posterior parts develop, then the animal becomes a functional hermaphrodite. However, hermaphroditism being characterised as functional needs to be validated by more reproduction studies (Patzner 1998).

Systems:

Marine

Threats [top]

Major Threat(s):	There are no known threats to this species.

Major Threat(s):

There are no known threats to this species.

Conservation Actions [top]

Conservation Actions:	This species is found within Galápagos Marine Reserve so it is potentially safeguarded through enforcement activities. More research needed on its biology, population size, distribution and potential threats.

Conservation Actions:

This species is found within Galápagos Marine Reserve so it is potentially safeguarded through enforcement activities. More research needed on its biology, population size, distribution and potential threats.

Bibliography [top]

	IUCN. 2011. IUCN Red List of Threatened Species (ver. 2011.1). Available at: http://www.iucnredlist.org. (Accessed: 16 June 2011). McMillan, C.B. 1999. Three new species of hagfish (Myxinidae, Eptatretus) from the Galápagos Islands. Fisheries Bulletin 97(1): 110-117. Mincarone, M.M. and McCosker, J.E. 2004. Eptatretus lakeside sp. nov., a new species of five-gilled hagfish (Myxinidae) from the Galápagos Islands. Proceedings of the California Academy of Science 55(6): 162-168. Patzner, R.A. 1998. Gonads and reproduction in hagfishes. In: J.M. Jørgensen, J.P. Lomholt, R.E. Weber, and H. Malte (eds), The biology of hagfishes, pp. 378-395. Chapman & Hall, London.

IUCN. 2011. IUCN Red List of Threatened Species (ver. 2011.1). Available at: http://www.iucnredlist.org. (Accessed: 16 June 2011).

McMillan, C.B. 1999. Three new species of hagfish (Myxinidae, Eptatretus) from the Galápagos Islands. Fisheries Bulletin 97(1): 110-117.

Mincarone, M.M. and McCosker, J.E. 2004. Eptatretus lakeside sp. nov., a new species of five-gilled hagfish (Myxinidae) from the Galápagos Islands. Proceedings of the California Academy of Science 55(6): 162-168.

Patzner, R.A. 1998. Gonads and reproduction in hagfishes. In: J.M. Jørgensen, J.P. Lomholt, R.E. Weber, and H. Malte (eds), The biology of hagfishes, pp. 378-395. Chapman & Hall, London.

Citation:	Mincarone, M.M. 2011. Eptatretus wisneri. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 24 April 2014.
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