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Castelnau's jawfish (Opistognathus castelnaui) — Opistognathidae

Castelnau's jawfish

Opistognathus castelnaui

The Castelnau's jawfish (Opistognathus castelnaui) is a saltwater fish of the family Opistognathidae that grows up to 25 cm.

Length
25 cm
Water
Saltwater
Depth
20.0–100.0 m
Body shape
Elongated (eel-like)
Substrate
Sand / mud bottom
Danger
Harmless

Description

The Castelnau's jawfish is a jawfish (Opistognathidae) from coastal waters of northern Australia. The species grows to about 25 cm and has a stocky forebody with a very large mouth and large eyes. As a bottom-dweller it digs and lines a vertical burrow with pebbles, from which it protrudes its forebody to snap at passing zooplankton; when threatened it withdraws backwards into the burrow. The male broods the eggs in his mouth. The fish is harmless to humans.

Frequently asked questions

How do you recognise the Castelnau's jawfish?

The Castelnau's jawfish has an elongate, eel-like body and is mainly brown.

Where does the Castelnau's jawfish live?

The Castelnau's jawfish lives in the sea (marine waters) and is mostly found around sand or mud bottom.

How big does the Castelnau's jawfish get?

The Castelnau's jawfish grows to a maximum of about 25 cm.

Is the Castelnau's jawfish dangerous to humans?

No, the Castelnau's jawfish is harmless to humans.

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All data

Identification

Dutch name
Castelnaus kaakvis sourced
English name
Castelnau's jawfish sourced
Scientific name
Opistognathus castelnaui
Family
Opistognathidae

Appearance

Size class
Medium verified
Max length (cm)
25.0 verified
Body shape
Elongated (eel-like) sourced
Dominant colour
Brown sourced
Tail shape
Rounded inferred

Habitat & distribution

Water type
Saltwater sourced
Substrate
Sand / mud bottom sourced
Min depth (m)
20.0 verified
Max depth (m)
100.0 verified
Origin
Native inferred

Behaviour & biology

Territorial
Yes inferred
Reproduction
Separate sexes inferred
Sexual dimorphism
No inferred

For anglers

Fishing method
Bodemvissen met natuurlijk aas (worm, garnaal of vis) op of vlak boven de bodem. inferred
Regulations source
FishBase ↗ inferred

Safety

Danger to humans
Harmless verified

Status & sources

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

Same genus Opistognathus

More from the family Opistognathidae

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