About Canthigaster amboinensis (Bleeker, 1864)
Canthigaster amboinensis has an overall quite rotund body, but it is a fast swimmer that can be hard to approach. This species can grow to a total length of 15 cm (5.9 inches). It can be identified by its dark brown base color, blue-green lines that radiate from the eyes, dark blue spots and lines on the cheeks, and iridescent light blue to white spots covering the head and body. These iridescent spots are not present from the anus to the lower jaw. C. amboinensis is one of over 30 species in the genus Canthigaster. It is rarely included in scientific research studies, and can be difficult to distinguish from other closely related species.
This species is found across the tropical Indo-Pacific region. Adult pairs are most often found around boulders in shallow near-shore areas and on reef patches. Females typically occupy a home range of 25 m2, while males occupy a home range of 100 to 175 m2. Juveniles of this species are secretive, and are usually only found in holes near outer reef flats and reef margins.
During reproduction, males fertilize eggs while hovering near the nesting area where the female deposits her eggs. At a single spawning site, the female lays her eggs over approximately 20 to 30 seconds. Females of C. amboinensis are recorded to have around five separate spawning bouts, each lasting 45 to 80 seconds.
