Myxini (hagfishes) > Myxiniformes
(Hagfishes) > Myxinidae
(Hagfishes) > Eptatretinae
Etymology: Eptatretus: Greek, epta = seven + Greek, tretos, -e, -on = with holes (Ref. 45335); wisneri: Named after Robert L. Wisner, Scripps Institution of Oceanography, University of California, for his contribution to hagfish biology (Ref. 31545)
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; non-migratory; depth range 330 - 412 m (Ref. 51420), usually - m (Ref. ). Deep-water; 0°C -
Northwest Pacific: southeast of Taiwan.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 33.5 cm TL male/unsexed; (Ref. 31276)
Morphology | Morphometrics
Brachial length 4.58% of total length; six pairs of gill pouches and gill apertures, gill apertures closely spaced in straight line; external opening of pharyngocutaneous duct (PCD) confluent with the most posterior left gill aperture (51 of 59 specimens examined), and much larger than other apertures; fused unicuspid teeth; eye spots present but not clear (Ref. 31545).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Copulatory organ absent. 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 (Ref. 51361 ).
Fernholm, B., 1998. Hagfish systematics. p. 33-44. In J.M. Jørgensen, J.P. Lomholt, R.E. Weber and H. Malte (eds.) The biology of hagfishes. Chapman & Hall, London. 578 p. (Ref. 31276)
IUCN Red List Status (Ref. 124695)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00204 (0.00095 - 0.00438), b=2.92 (2.73 - 3.11), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 4.2 ±0.5 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Fec assumed to be <100).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (26 of 100) .