Forcipiger flavissimus is one of the 3 members belonging to the genus Forcipiger, which together with 11 additional genera make up the butterflyfishes family (Chaetodontidae) in which there are currently a total of 129 described species. It is the most widely distributed of all the butterflyfishes, covering territories of both the Indian Ocean and the Pacific Ocean. It is present from the waters of South Africa and Madagascar, the Red Sea and Persian Gulf, Maldives, to Australia, Indonesia, New Guinea, and as far south as Japan. In the Pacific it is present as far as Easter Island, Hawaii, Galapagos and even in the Mexican Pacific coast and the Gulf of California. It is associated with coral environments up to 50 meters deep.
The body of Forcipiger flavissimus is tall, laterally compressed, relatively oval and has an elongated rostrum, with a tubular snout ending in a small mouth, which gives rise to the colloquial name forcepsfish given the shape of the mouth. They can grow up to 15 cm in total length. The dorsal fin has 12-13 spines with strongly indented interspinal membranes, and 19-25 soft rays. The anal fin has 3 spines and 17-19 soft rays. The ventral fins have only a single spine and 5 soft rays, while the caudal fin is more or less truncated.
As for the coloration of Forcipiger flavissimus, the dominant color of the body is bright yellow. Only the head region is a different color. The upper half of the head, horizontally across the eyes, is dark brown, while the lower triangle of the rostrum is white. The dorsal, anal and ventral fins are completely yellow, while the pectoral and caudal fins are translucent. The dorsal and anal fins are notable because the outermost regions of the soft rays are electric blue. It is also striking a black spot located at the rear end of the anal fin, next to the caudal peduncle, which is an ocellar spot in order to mislead potential predators.
It is very common and easy to confuse specimens of Forcipiger flavissimus with the evolutionarily close but less frequent Forcipiger longirostris. The differences between these two species may go unnoticed, although there are some features that make their differentiation possible. In the case of Forcipiger flavissimus the snout is not as long as that of Forcipiger longirostris (up to 1.5 times longer in this species), and the mouth is somewhat larger. Another difference, but in this case distinctive of Forcipiger longirostris is the presence of a black mottling in the throat and chest region, therefore, its absence would be indicative of being in front of Forcipiger flavissimus. The third trait can go completely unnoticed, since Forcipiger flavissimus has between 1 and 2 more spines on the dorsal fin.
Forcipiger flavissimus is usually a solitary species but it is also possible to find it in small groups. During the reproductive season they form pairs that will release eggs and sperm into the water column, so that fertilization occurs and the dominant currents spread their small eggs over a vast territory.Photos: