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Butterfly blenny (Blennius ocellaris) — Blenniidae

Butterfly blenny

Blennius ocellaris
Family: Blenniidae
LC · Least Concern

The Butterfly blenny (Blennius ocellaris) is a saltwater fish of the family Blenniidae that grows up to 20 cm.

Length
20 cm
Water
Saltwater
Depth
10.0–400.0 m
Diet
Carnivore
Behaviour
Solitary
Activity
Diurnal
Body shape
Elongated (eel-like)
Substrate
Sand / mud bottom
Danger
Harmless
Edibility
Not eaten

Description

The butterfly blenny is a striking blenny of the family Blenniidae reaching about 20 cm. Characteristic is the tall, sail-like first dorsal fin with a large black eyespot ringed in pale; a fringed skin crest stands between the eyes. The brownish body bears several dark cross-bars. Unlike most blennies, which live in the tidal zone, the butterfly blenny stays at somewhat greater depth on sand, mud and shell bottoms of the north-eastern Atlantic and the Mediterranean. As a bottom-dweller it hunts small crustaceans and invertebrates. The male guards the eggs laid in an empty shell, cavity or even a discarded object. Because of its small size it has no fishery importance.

Frequently asked questions

How do you recognise the Butterfly blenny?

The Butterfly blenny has an elongate, eel-like body, is mainly brown and shows a vertical stripes pattern.

Where does the Butterfly blenny live?

The Butterfly blenny lives in the sea (marine waters) and is mostly found around sand or mud bottom.

How big does the Butterfly blenny get?

The Butterfly blenny grows to a maximum of about 20 cm.

Is the Butterfly blenny dangerous to humans?

No, the Butterfly blenny is harmless to humans.

Is the Butterfly blenny edible?

The Butterfly blenny is not usually eaten.

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All data

Identification

Dutch name
Vlinderslijmvis inferred
English name
Butterfly blenny verified
Scientific name
Blennius ocellaris
Family
Blenniidae
Other names
Butterfly blenny; Butterfly-blenny verified

Appearance

Size class
Medium verified
Max length (cm)
20.0 verified
Body shape
Elongated (eel-like) sourced
Dominant colour
Brown sourced
Pattern
Vertical bars sourced
Tail shape
Rounded inferred
Mouth position
Terminal inferred
Lips
Thick / fleshy inferred
Barbels
No verified
Dorsal fins
One continuous sourced
Dorsal spines
Yes verified

Habitat & distribution

Water type
Saltwater verified
Substrate
Sand / mud bottom sourced
Min depth (m)
10.0 verified
Max depth (m)
400.0 verified
Origin
Native verified

Behaviour & biology

Diet
Carnivore verified
Social behaviour
Solitary verified
Territorial
Yes verified
Activity
Diurnal inferred
Reproduction
Separate sexes verified
Sexual dimorphism
No verified

For anglers

Edibility
Not eaten verified
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 sourced

Status & sources

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

Same genus Blennius

More from the family Blenniidae

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