About Chaetodon interruptus Ahl, 1923
The yellow teardrop butterflyfish (Chaetodon interruptus Ahl, 1923) has a bright yellow, disc-shaped, laterally compressed body. It has a large black spot on its upper flank, a black vertical bar through the eye, and a second black vertical bar at the rear margin that extends from the back of the soft-rayed section of the dorsal fin to the anal fin. The tail is white, and the tail fin is transparent. Paler chevron-shaped markings run vertically down its flanks. Small juvenile fish have a white ring surrounding the black blotch on their flank; this blotch is rounder and less teardrop-shaped than the adult marking, and the black color has a blue tint. As the fish grows, the outer white ring turns yellow, and the mark develops a teardrop shape. This species has 12–13 spines and 21–23 soft rays in its dorsal fin, and 3 spines and 18–20 soft rays in its anal fin. It reaches a maximum total length of 20 centimetres (7.9 in). This butterflyfish is distributed across the Indian Ocean. It occurs along the East African coast from Somalia and Socotra south to South Africa, and east as far as the coast of Sumatra and western Thailand. Its range also includes most Indian Ocean islands and southern India. It inhabits a range of habitats from coral reef flats to deep slopes. Adults are most commonly found in pairs, but will occasionally forage in small schools. This is an oviparous species, where males and females form breeding pairs. It is omnivorous with a varied diet that includes hard and soft coral fragments, sponges, polychaetes, and filamentous algae.
