Acanthurinae

Acanthurinae
Acanthurus sohal
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Acanthuridae
Subfamily:	Acanthurinae

Acanthurinae is a subfamily of fish belonging to the family Acanthuridae, including 55 species in four genera.

Among the species of the genera Acanthurus and Zebrasoma there are small anatomical differences: the first are disc-shaped and have a crescent-shaped tail, while the Zebrasoma have ovaloid profile and a protruding muzzle.

The fry is transparent and has 13 venomous spines on the spine. The appearance changes when the specimen reaches the size of about 10 cm.

Like all species of the family Acanthuridae, Acanthurinae have a retractable spine on the caudal peduncle. It is very sharp (as a lancet) and it is used as an extreme defense. To emphasize the importance ot this spine many species have showy aposematic colors in the caudal peduncle (or even directly a colored lancet).

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Wikipedia