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Jespersen's onejaw (Monognathus jesperseni) — Monognathidae

Jespersen's onejaw

Monognathus jesperseni
Family: Monognathidae

The Jespersen's onejaw (Monognathus jesperseni) is a saltwater fish of the family Monognathidae that grows up to 11 cm.

Length
10.9 cm
Water
Saltwater
Depth
0–3000.0 m
Body shape
Snake-like
Substrate
Open water
Danger
Harmless

Description

Jespersen's onejaw is an extremely rare, small deep-sea eel (Monognathidae) from the bathypelagic zone of the ocean. The species grows to about 11 cm and has a soft, eel-like, pale body notable for lacking the upper jaw; instead it has a venom tooth at the front of the mouth with which it injects prey. In the perpetually dark deep sea it seizes passing crustaceans and small fish. The fish is harmless to humans.

Frequently asked questions

How do you recognise the Jespersen's onejaw?

The Jespersen's onejaw has a snake-like body and is mainly white.

Where does the Jespersen's onejaw live?

The Jespersen's onejaw lives in the sea (marine waters) and is mostly found around open water.

How big does the Jespersen's onejaw get?

The Jespersen's onejaw grows to a maximum of about 11 cm.

Is the Jespersen's onejaw dangerous to humans?

No, the Jespersen's onejaw is harmless to humans.

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All data

Identification

Dutch name
Jespersens eenkaakaal sourced
English name
Jespersen's onejaw sourced
Scientific name
Monognathus jesperseni
Family
Monognathidae

Appearance

Size class
Small verified
Max length (cm)
10.9 verified
Body shape
Snake-like sourced
Dominant colour
White sourced
Tail shape
Straight inferred

Habitat & distribution

Water type
Saltwater sourced
Substrate
Open water sourced
Max depth (m)
3000.0 verified
Origin
Native inferred

Behaviour & biology

Territorial
No inferred
Reproduction
Separate sexes inferred
Sexual dimorphism
No inferred

For anglers

Fishing method
Klein van stuk en nauwelijks een hengelsportdoel; wordt vooral incidenteel of als aasvis gevangen. inferred
Regulations source
FishBase ↗ inferred

Safety

Danger to humans
Harmless verified

Status & sources

Sources
FishBase via GBIF (DwC-A), CC-BY-NC 4.0

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