The undefined (Melichthys indicus), commonly referred to as the black-finned triggerfish, exhibits a brown body and black fins with distinctive white lines at the base of the dorsal and anal fins. It is predominantly found throughout the 🌊 Indian Ocean and can reach a maximum length of 25 cm (10 in).
In terms of diet, the undefined primarily consumes hard-shelled molluscs and echinoderms, although some individuals may also feed on algae and zooplankton. While they exhibit aggression in protecting their eggs, they generally pose no threat otherwise. When it comes to keeping them as pets, undefined are generally manageable, although certain individuals may display aggression towards other fish.
It is important to note that the undefined should not be mistaken for the Hawaiian black triggerfish or black durgon (Melichthys niger), as this often occurs within the trade. Despite their similar shape and coloration, it is worth highlighting that the undefined has never been documented near Hawaii.
Why it's threatened
Harvesting of this species for the aquarium trade may cause localised population declines. Ongoing coral reef degradation may also impact this species.
Threat classification from the IUCN Red List.
