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🌊 Marine Least Concern 🌡️ Deep-water

McCosker's hagfish

Eptatretus mccoskeri McMillan, 1999
Max Length
32 cm
Max Weight
-
Lifespan
-
Trophic Level
4
Depth
155–215 m
Climate
Deep-water
Resilience
Low
Vulnerability
30.00/100
Typical Length
-
Depth Zone
deep-water

📖 Overview

McCosker's hagfish (Eptatretus mccoskeri), first described by McMillan, 1999 is a medium-sized fish in the family Myxinidae (order Myxiniformes). Adults typically reach 32.00 cm in maximum length. It inhabits marine coastal and open-ocean environments. Recorded depth range: 155 to 215 metres. It occurs in Deep-water waters. Diet is predominantly piscivorous, targeting other fish and larger prey. On the IUCN Red List, it is classified as Least Concern.

Scientific Name
Eptatretus mccoskeri
Authority
McMillan, 1999
Habitat
Marine
Climate
Deep-water
IUCN Status
LC
Max Length
32 cm
Depth Range
155–215 m
Trophic Level
4
Resilience
Low
Vulnerability
30.00/100
Migration
Non-migratory
Salinity
30–40 ppt

🔬 Taxonomy

Kingdom
Animalia
Phylum
Chordata
Class
Hagfishes
Myxini
Order
Myxiniformes
Myxiniformes
Family
Myxinidae
Myxinidae
Genus
Eptatretus
Eptatretus
Species
McCosker's hagfish
Eptatretus mccoskeri

🐟 Physical Description

This species is distinguished from its congeners, except Eptatretus poicilus by the following characters: gill apertures 8 pairs (7 in one specimen), well-spaced and arranged in a near straight line; a 3/3 multicusp pattern of teeth; differs from Eptatretus poicilus by its number of trunk pores 38-43 (vs. 45-50), by the number of total pores 69-75 (vs. 78-86) and by its colour pattern, with body purple to purplish brown (vs. body strongly mottled with pale brown, dark brown and white-beige) . : eel-like; Cross section: oval.

🌀 Behaviour

Behavioural data for McCosker's hagfish is currently being reviewed.

🦐 Diet

small fish
crustaceans
cephalopods

🥚 Reproduction

🐣 Oviparous 📦 Batch Spawner
Spawning Season
spring-summer
Spawn Location
Pelagic
Fertilization
External

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 .

🌍 Habitat & Distribution

Marine; demersal; non-migratory; depth range 155 - 215 m . Deep-water Southeast Pacific: Galapagos Islands.

🌿 Ecology

Zone Preferences
🌊 Marine 🌑 Deep Water ⬇️ Benthic
Migration
Non-migratory
Trophic Level
4±0.7

📐 Morphometrics

Length–Weight Relationship: W = 0.00204 × L2.93 (TL)
Max TL
32cm

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2022

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
30.00/100
Low vulnerability
Trophic Level
4
Apex / Top predator
Climate Zone
Deep-water
Described By
McMillan, 1999

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 1 records indexed .

Occurrence density from GBIF View GBIF records ↗

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