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Squarenose unicornfish (Naso mcdadei) — Acanthuridae

Squarenose unicornfish

Naso mcdadei
Family: Acanthuridae

The Squarenose unicornfish (Naso mcdadei) is a saltwater fish of the family Acanthuridae that grows up to 75 cm.

Length
75 cm
Water
Saltwater
Depth
5.0–65.0 m
Diet
Herbivore
Activity
Diurnal
Body shape
Torpedo-shaped
Substrate
Stone or rock
Danger
Can cause injury

Description

The squarenose unicornfish is a surgeonfish (Acanthuridae) from the Indo-West Pacific. The species grows to about 75 cm and has a deep, grey-blue body with an angular, square snout without a true horn. On the tail base it carries two pairs of sharp, scalpel-like bony keels. As a reef-dweller it hovers above deeper reef slopes and grazes weed and picks zooplankton. The tail keels can cause deep cuts when handled; otherwise the fish is harmless to humans.

Frequently asked questions

How do you recognise the Squarenose unicornfish?

The Squarenose unicornfish has a torpedo-shaped body and is mainly blue.

Where does the Squarenose unicornfish live?

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

How big does the Squarenose unicornfish get?

The Squarenose unicornfish grows to a maximum of about 75 cm.

Is the Squarenose unicornfish dangerous to humans?

The Squarenose unicornfish can cause injury; handle it with care.

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All data

Identification

Dutch name
Vierkantsneus-eenhoornvis sourced
English name
Squarenose unicornfish sourced
Scientific name
Naso mcdadei
Family
Acanthuridae
Other names
Squarenose unicornfish verified

Appearance

Size class
Large verified
Max length (cm)
75.0 verified
Body shape
Torpedo-shaped sourced
Dominant colour
Blue sourced
Tail shape
Crescent (lunate) inferred

Habitat & distribution

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

Behaviour & biology

Diet
Herbivore sourced
Territorial
No inferred
Activity
Diurnal inferred
Reproduction
Separate sexes inferred
Sexual dimorphism
No inferred

For anglers

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
Can cause injury verified

Status & sources

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

Same genus Naso

More from the family Acanthuridae

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