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Humboldt's glass knifefish (Eigenmannia humboldtii) — Sternopygidae

Humboldt's glass knifefish

Eigenmannia humboldtii
Family: Sternopygidae

The Humboldt's glass knifefish (Eigenmannia humboldtii) is a freshwater fish of the family Sternopygidae that grows up to 49 cm.

Length
48.6 cm
Water
Freshwater
Activity
Nocturnal
Body shape
Elongated (eel-like)
Substrate
Sand / mud bottom
Danger
Harmless

Description

Humboldt's glass knifefish is a weakly electric knifefish (Sternopygidae) from fresh water of northwestern South America. The species grows to about 40 cm and has an elongate, semi-translucent, silvery body with a very long anal fin along the belly with which it swims smoothly forwards and backwards. As a nocturnal fish it explores slow rivers and banks with a weak electric field in search of insect larvae and small invertebrates; the current cannot be felt by humans. The fish is harmless to humans.

Frequently asked questions

How do you recognise the Humboldt's glass knifefish?

The Humboldt's glass knifefish has an elongate, eel-like body and is mainly silver-grey.

Where does the Humboldt's glass knifefish live?

The Humboldt's glass knifefish lives in fresh water and is mostly found around sand or mud bottom.

How big does the Humboldt's glass knifefish get?

The Humboldt's glass knifefish grows to a maximum of about 49 cm.

Is the Humboldt's glass knifefish dangerous to humans?

No, the Humboldt's glass knifefish is harmless to humans.

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All data

Identification

Dutch name
Humboldts glas-mesvis sourced
English name
Humboldt's glass knifefish sourced
Scientific name
Eigenmannia humboldtii
Family
Sternopygidae

Appearance

Size class
Large verified
Max length (cm)
48.6 verified
Body shape
Elongated (eel-like) sourced
Dominant colour
Silver / grey sourced
Tail shape
Straight inferred

Habitat & distribution

Water type
Freshwater sourced
Substrate
Sand / mud bottom sourced
Origin
Native inferred

Behaviour & biology

Territorial
No inferred
Activity
Nocturnal sourced
Reproduction
Separate sexes inferred
Sexual dimorphism
No inferred

For anglers

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 verified

Status & sources

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

Same genus Eigenmannia

More from the family Sternopygidae

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