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Thornback cowfish (Lactoria fornasini) — Ostraciidae

Thornback cowfish

Lactoria fornasini
Family: Ostraciidae
LC · Least Concern

The Thornback cowfish (Lactoria fornasini) is a saltwater fish of the family Ostraciidae that grows up to 23 cm.

Length
23 cm
Water
Saltwater
Depth
5.0–132.0 m
Diet
Carnivore
Behaviour
Solitary
Activity
Diurnal
Body shape
Flat / disc-shaped
Substrate
Stone or rock
Danger
Venomous / poisonous
Edibility
Not eaten

Description

The thornback cowfish is a boxfish from the Indo-Pacific, from East Africa to Hawaii, north to Japan. The species grows to about 23 cm and has an angular body in a bony carapace, with a pair of forward horns above the eyes and a conspicuous spine on the back, from which it takes its name. It lives on reef and sandy bottoms and eats small bottom invertebrates. Like other boxfishes it secretes a toxic skin mucus (ostracitoxin) when stressed that can kill other fish; in parts of the tropics the flesh is considered poisonous. The IUCN assesses the species as Least Concern (LC).

Frequently asked questions

How do you recognise the Thornback cowfish?

The Thornback cowfish has a flattened, disc-shaped body, is mainly yellow-gold and shows a spots pattern.

Where does the Thornback cowfish live?

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

How big does the Thornback cowfish get?

The Thornback cowfish grows to a maximum of about 23 cm.

Is the Thornback cowfish dangerous to humans?

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

Is the Thornback cowfish edible?

The Thornback cowfish is not usually eaten.

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All data

Identification

Dutch name
Doornrug-koevis verified
English name
Thornback cowfish verified
Scientific name
Lactoria fornasini
Family
Ostraciidae
Other names
Boxfish; Cofferfish; Cowfish; Thornback boxfish; Thornback cow verified

Appearance

Size class
Medium verified
Max length (cm)
23.0 verified
Body shape
Flat / disc-shaped sourced
Dominant colour
Yellow / gold inferred
Pattern
Spots inferred
Tail shape
Rounded inferred
Mouth position
Terminal sourced
Lips
Thin sourced
Barbels
No sourced
Dorsal fins
One continuous sourced
Dorsal spines
No sourced

Habitat & distribution

Water type
Saltwater sourced
Substrate
Stone or rock sourced
Min depth (m)
5.0 verified
Max depth (m)
132.0 verified
Origin
Native verified

Behaviour & biology

Diet
Carnivore sourced
Social behaviour
Solitary sourced
Territorial
No sourced
Activity
Diurnal sourced
Reproduction
Separate sexes sourced
Sexual dimorphism
No sourced

For anglers

Edibility
Not eaten sourced
Fishing method
Vissen met natuurlijk aas (vis, garnaal, worm) of kunstaas dicht bij rif- en rotsstructuren. inferred
Regulations source
FishBase ↗ inferred

Safety

Danger to humans
Venomous / poisonous sourced

Status & sources

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

Same genus Lactoria

More from the family Ostraciidae

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