The lined butterflyfish (Chaetodon lineolatus) is a species of marine ray-finned fish. a butterflyfish belonging to the family Chaetodontidae, one of the largest species in the genus Chaetodon. It has a wide range from the Red Sea to South Africa and as far east as southern Japan and Hawaii.
Lined butterflyfish may grow up to 30 centimetres (12 in) long, which among Chaetodon is matched only by the saddle butterflyfish (C. ephippium), making them about as big as dinner plates. They are white in color, with thin black vertical bars which join a thick black band at the base of the tail and dorsal fin. The tail, dorsal, and anal fins are yellow.
The species occurs along the east coast of Africa including the Red Sea and Mozambique Channel, throughout Northern Australia including the Coral Sea, Gulf of Carpentaria, and Timor Sea, and throughout West Indo-Pacific including the Java Sea, South China Sea, Philippine Sea, and Celebes Sea.
This uncommon fish is found in pairs or swimming alone, or occasionally in spawning aggregations. It occurs between 2 and 50 m depth, in coral-rich areas of reefs and lagoons.
Coral polyps, small anemones, algae and invertebrates make up the lined butterflyfish's diet. It is known to be territorial. This territorialism is connected to their highly specific feeding habits that is located on certain areas.
The species can reach an age of up to ten years.
Very little is known about the spawning of butterflyfish as a whole, however it is believed that they spawn near their feeding habitats during new moon. The lined butterflyfish mates in lifelong monogamous relationships. However, the male chooses to either stay with its one mate or leave and find another mate. This appears to maximize their fecundity. Lined butterflyfish are social maters, meaning they spend time with their mate outside of just spawning often living together in the same habitat. The species however exhibits little to no parental care to their young.
The species is classified as Least Concern by the IUCN due to its wide distribution and presence in protected areas. Its biggest threat is the loss of habitat via coral reef degradation, due to the overdevelopment and over-use of coral reefs and their resources.
Corals and members of the family Chaetodontidae were thought to have a commensal relationship. Coral provides the butterflyfish with food and shelter while coral gets little to nothing in return. However, upon further investigation it seems that C. lineolatus and other corallivore members of Chaetodontidae pose a bigger threat to coral than previously understood. Corallivores disturb the growth of coral species. This predation may have a long-term effect of on reef biodiversity. The loss of habitat affects reef fishes, including the Chaetodontidae, by making them more prone to predation from larger fishes.
