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Crazy fish (Butis butis) — Eleotridae

Crazy fish

Butis butis
Family: Eleotridae
LC · Least Concern

The Crazy fish (Butis butis) is a fish that lives in both fresh and salt water of the family Eleotridae that grows up to 15 cm.

Length
15 cm
Water
Euryhaline
Diet
Carnivore
Behaviour
Solitary
Activity
Nocturnal
Body shape
Elongated (eel-like)
Substrate
Sand / mud bottom
Danger
Harmless
Edibility
Rarely eaten

Description

The duckbill sleeper is a fish of the family Eleotridae (sleeper gobies) widely distributed across the Indo-Pacific. The species has an elongate, brown mottled body with a pointed, beak-like head and reaches about 15 cm. It inhabits brackish mangrove estuaries, lagoons and the lower reaches of rivers, usually on mud bottoms among vegetation, and sometimes ascends further upstream. Remarkably it can swim and hover upside down, hence its English nickname 'crazy fish'. It is an ambush predator feeding on small fishes and crustaceans.

Frequently asked questions

How do you recognise the Crazy fish?

The Crazy fish has an elongate, eel-like body, is mainly brown and shows a marbled pattern.

Where does the Crazy fish live?

The Crazy fish lives in both fresh and salt water and is mostly found around sand or mud bottom.

How big does the Crazy fish get?

The Crazy fish grows to a maximum of about 15 cm.

Is the Crazy fish dangerous to humans?

No, the Crazy fish is harmless to humans.

Is the Crazy fish edible?

The Crazy fish is rarely eaten.

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All data

Identification

Dutch name
Eendsnavel-slaapgrondel sourced
English name
Crazy fish verified
Scientific name
Butis butis
Family
Eleotridae
Other names
Crimsontip gudgeon; Crimson-tipped flathead gudgeon; Crimson-tipped flathead-gudgeon; Crimson-tipped flathead-sleeper; Crimson-tipped gudgeon verified

Appearance

Size class
Small verified
Max length (cm)
15.0 verified
Body shape
Elongated (eel-like) sourced
Dominant colour
Brown inferred
Pattern
Marbled inferred
Tail shape
Rounded inferred
Mouth position
Terminal inferred
Lips
Thin inferred
Barbels
No sourced
Dorsal fins
Two separate inferred
Dorsal spines
Yes sourced

Habitat & distribution

Water type
Euryhaline sourced
Substrate
Sand / mud bottom sourced
Origin
Native sourced

Behaviour & biology

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

For anglers

Edibility
Rarely eaten sourced
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 sourced

Status & sources

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

Same genus Butis

More from the family Eleotridae

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