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Asian swamp eel (Monopterus albus) — Synbranchidae

Asian swamp eel

Monopterus albus
Family: Synbranchidae
LC · Least Concern

The Asian swamp eel (Monopterus albus) is a brackish-water fish of the family Synbranchidae that grows up to 100 cm.

Length
100 cm
Water
Brackish
Depth
3.0–? m
Diet
Carnivore
Behaviour
Solitary
Activity
Nocturnal
Body shape
Snake-like
Substrate
Sand / mud bottom
Danger
Harmless
Edibility
Commonly eaten

Description

The Asian swamp eel is an elongate, eel-like freshwater fish from East and Southeast Asia that grows to about one metre. It lacks pectoral and pelvic fins and has greatly reduced, continuous dorsal and anal fins. The species lives in swamps, rice fields, ditches and slow-flowing waters and can breathe air through its skin and mouth cavity, allowing it to survive dry spells and low-oxygen water. It is a nocturnal predator feeding on invertebrates and small fishes. Notably, the species first functions as a female and later changes into a male. Outside Asia it is locally invasive.

Frequently asked questions

How do you recognise the Asian swamp eel?

The Asian swamp eel has a snake-like body, is mainly brown and shows a plain pattern.

Where does the Asian swamp eel live?

The Asian swamp eel lives in brackish water and is mostly found around sand or mud bottom.

How big does the Asian swamp eel get?

The Asian swamp eel grows to a maximum of about 100 cm. On average the species is around 40 cm.

Is the Asian swamp eel dangerous to humans?

No, the Asian swamp eel is harmless to humans.

Is the Asian swamp eel edible?

Yes, the Asian swamp eel is commonly eaten.

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All data

Identification

Dutch name
Aziatische moerasaal sourced
English name
Asian swamp eel verified
Scientific name
Monopterus albus
Family
Synbranchidae
Other names
Asian swamp eel; Belut; Lai; Rice (paddy) field eel; Rice eel verified

Appearance

Size class
Extra large verified
Max length (cm)
100.0 verified
Average length (cm)
40.0 verified
Body shape
Snake-like sourced
Dominant colour
Brown inferred
Pattern
Plain inferred
Tail shape
Straight inferred
Mouth position
Terminal inferred
Lips
Thin inferred
Barbels
No sourced
Dorsal fins
One continuous inferred
Dorsal spines
No sourced

Habitat & distribution

Water type
Brackish sourced
Substrate
Sand / mud bottom sourced
Min depth (m)
3.0 verified
Origin
Native sourced

Behaviour & biology

Diet
Carnivore sourced
Social behaviour
Solitary inferred
Territorial
No inferred
Activity
Nocturnal inferred
Reproduction
Protogynous (female first) sourced
Sexual dimorphism
No inferred

For anglers

Edibility
Commonly eaten sourced
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 Monopterus

More from the family Synbranchidae

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