Genicanthus melanospilos

Lore & Background

Genicanthus melanospilos was first formally described in 1857 as Holocanthus melanospilos by the Dutch ichthyologist and herpetologist Pieter Bleeker, with the type locality given as Ambon Island in Indonesia. The specific name is a compound of melanos meaning 'black' and spills meaning 'spot', referring to the black spot on the male's chest. The species shows sexual dichromatism: males have a bluish white body with many reddish black vertical stripes, yellow spots on the dorsal, caudal and anal fins, a light yellow caudal fin with blue margins and long filamentous lobes, and a sizeable black spot on the breast near the base of the pelvic fins. Females have a yellow dorsal half and bluish white ventral half, with a bluish tail bearing a black stripe along its upper and lower margins. In both sexes, the forked tail narrows at its base to create a 'swallow tail'.

Reader's Guide

Genicanthus melanospilos is a widespread species found in the eastern Indian Ocean and western Pacific Ocean, ranging throughout the Malay Archipelago into the southwestern Pacific as far east as Fiji, north to the Ryukyu Islands, and south to Australia. In Australian waters it occurs at the Cocos (Keeling) Islands, Christmas Island, Ashmore Reef in the Timor Sea, and the Great Barrier Reef off Cairns, Queensland. It inhabits depths between 20 and 80 metres, in areas rich in coral on the outer slopes of reefs and drop-offs. Adults are normally organised as small harems made up of a male and several females, and they feed on zooplankton in the water over reefs. Like all other angelfish, the spotbreast angelfish is a protogynous hermaphrodite, with all individuals initially female and the dominant ones changing to males. The species is common in the aquarium trade.

Did You Know?

• This species is a protogynous hermaphrodite: all individuals start as females and dominant ones change to males.
• It is found at depths between 20 and 80 metres on outer coral reef slopes and drop-offs.