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Bluetail trunkfish (Ostracion cyanurus) — Ostraciidae

Bluetail trunkfish

Ostracion cyanurus
Family: Ostraciidae

The Bluetail trunkfish (Ostracion cyanurus) is a saltwater fish of the family Ostraciidae that grows up to 15 cm.

Length
15 cm
Water
Saltwater
Body shape
Torpedo-shaped
Substrate
Stone or rock
Danger
Venomous / poisonous
Edibility
Not eaten

Description

The bluetail trunkfish is a boxfish (Ostraciidae) from the Red Sea and western Indian Ocean. The species grows to about 15 cm and has a box-shaped, armoured body of bony plates; males are yellow-blue with a bright blue tail base, females darker with blue spots. As a slow reef-dweller it picks algae, sponges and small invertebrates. When stressed the skin releases the toxin ostracitoxin, which can kill other fish in a confined space. The fish is harmless to humans in normal contact but should not be eaten.

Frequently asked questions

How do you recognise the Bluetail trunkfish?

The Bluetail trunkfish has a torpedo-shaped body and is mainly blue.

Where does the Bluetail trunkfish live?

The Bluetail trunkfish lives in the sea (marine waters) and is mostly found around stony or rocky ground.

How big does the Bluetail trunkfish get?

The Bluetail trunkfish grows to a maximum of about 15 cm.

Is the Bluetail trunkfish dangerous to humans?

The Bluetail trunkfish is venomous — handle spines with care and seek medical help after a sting if needed.

Is the Bluetail trunkfish edible?

The Bluetail trunkfish is not usually eaten.

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All data

Identification

Dutch name
Blauwstaart-koffervis sourced
English name
Bluetail trunkfish sourced
Scientific name
Ostracion cyanurus
Family
Ostraciidae
Other names
Bluetail trunkfish verified

Appearance

Size class
Small verified
Max length (cm)
15.0 verified
Body shape
Torpedo-shaped sourced
Dominant colour
Blue sourced
Tail shape
Rounded inferred

Habitat & distribution

Water type
Saltwater sourced
Substrate
Stone or rock sourced
Origin
Native inferred

Behaviour & biology

Territorial
No inferred
Reproduction
Separate sexes inferred
Sexual dimorphism
No inferred

For anglers

Edibility
Not eaten sourced
Fishing method
Geen doelsoort voor de hengelsport; hooguit incidentele vangst of bruikbaar als aasvisje. inferred
Regulations source
FishBase ↗ inferred

Safety

Danger to humans
Venomous / poisonous verified

Status & sources

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

Same genus Ostracion

More from the family Ostraciidae

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