Orange-lined Triggerfish

Description:

Balistapus undulatus, known commonly as the orange-lined triggerfish, orange-striped triggerfish and undulated triggerfish, is a demersal marine fish belonging to the family Balistidae, the triggerfishes. It is the only member of the monotypic genus Balistapus. It grows up to 30 cm long. Its body has a stock appearance, oval shape and compressed laterally. The head is large and is about one third of the body length. The mouth is small and terminal and it has strong teeth. The first dorsal fin has three spines, one of which is longer and stronger. It is erectile and kept in a dorsal furrow at rest. The second dorsal fin is similar in shape and size to the anal fin, which is symmetrically opposed to it. The pelvic fin is reduced to a ventral protrusion. The body is dark green with orange lines. The male loses the lines on his snout as he matures. There is a black blotch on the caudal peduncle, and the caudal fin is orange

Habitat:

It is widely distributed throughout the tropical and subtropical waters of the Indian Ocean and the western Pacific. It inhabits coral reefs, lagoons and external reef slopes at depths up to 50 meters. This triggerfish is diurnal, solitary, and territorial. It can be aggressive with other fish. It erects its first dorsal spine to intimidate opponents and predators.

Notes:

This beautiful triggerfish can be aggressive especially during nesting/breeding season. They built their 'egg nest' with coral rubble which they then guarded. During this period, they will be very protective and will 'attack' other fishes and even Divers if approach too close to them.