Latin name

Ostracion cyanurus

Other name

Arabian trunkfish or Red Sea boxfish.

Identification

Females of the bluetail trunkfish have a slightly concave dorsal profile of the head, whereas males have a convex profile. The lips and chin are fleshy and protrude forward.

These fish, like medieval knights, are clad in armor. From their bony box, only the lips, fins, and tail protrude.

Features of fish fins

The dorsal and anal fins have 9 soft rays each, and the caudal fin has 10 rays, of which 8 are branched.

Fish coloring

The species name, cyanurus, means "blue tail" and refers to the blue color of this fish's caudal fin. Adult males are typically dark blue with spots on the sides and lower part of the body and greenish-yellow on the upper part of the body, without spots. Females are yellow with blue spots and red cheeks.

Distribution

They are distributed in the western Indian Ocean, where they are found in the Red Sea and around the Arabian Peninsula in the Persian Gulf, east to eastern Iran.

Habitat

A marine tropical species. It inhabits areas with moderate coral growth at depths of 5 to 50 meters (16 to 164 feet).

Size

The bluetail trunkfish has a known maximum total length of 15 cm (6 inches).

Behavior

A solitary species that stays close to shelter. If the fish feels threatened, it releases a toxin called pahutoxin or ostracitoxin into the water as a defense.

Food and feeding habits

They feed on corals, which make up the majority of their diet. They also eat invertebrates, sea urchins, crabs, and mollusks.

Reproduction

The apparent absence of young males may indicate that all these fish are born as females, transitioning into males with age.

Fishing

It is not a target of fisheries and is considered a species of least concern.

Relationship with a person

The bluetail trunkfish is harmless. It is not an edible fish for humans. It is available for sale as an aquarium pet.