The Chaetodon madagaskariensis is also known as the Indian Ocean Chevron Butterflyfish, Madagascar Butterflyfish, Pearlscale Butterflyfish, Pearly Butterflyfish or Seychelles Butterflyfish.
It has a concave dorsal head profile, ctenoid scales (scales with comb-like edge), it has a whitish to pale grey oval shaped body and pointed nose. It is distinguished by a broad orange band across the rare of the body and 5 – 6 chevron shaped streaks on the body. A black bar lined by white is present between the eyes, on the forehead and start of dorsal fin. The base of its caudal fin is white, followed by orange and then a white rim. It grows to a maximum size of 13cm. Sexual dimorphism (difference in appearance) is not prominent, both male and female display bright colours.
This species is distributed across the Indian Ocean, from East Africa, including Port Elizabeth to South Africa, Cocos-keeling and Christmas Islands and north to Sri Lanka.
It is found on rocky or coral covered reefs of lagoons and on outer slopes. It is often seen near drop offs and steep slopes at depths of between 10m to 120m.
It is a facultative corallivore (it does not only feed on corals) and its diet also consists of algae and invertebrates.
Adults usually form pairs during breeding. Females swell with eggs and spawning occurs in the water column where males fertilise the eggs. Spawning is believed to take place with respect to lunar cycles but more research is required. A bony plate forms over the head area of the larvae when they hatch. The larvae are called “tholichthys” and grow to about 22mm before they become juvenile fish.
According to the IUCN Red list, this species is categorised as being of ‘Least Concern’ as it is common and widespread with no major threats. It is collected for the aquarium trade, however, there are no impact on the global population. No conservation measures are in place for this species. It is present in many MPAs.
This species nibbles at clams, including the giant clams, Tridacna spp. It has a strong preference for tubeworms as well.