The Easter Island butterflyfish (''Chaetodon litus'') or white-tip butterflyfish, is a species of subtropical

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

in the family Chaetodontidae. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the seas around

Easter Island Easter Island (, ; , ) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is renowned for its nearly 1,000 extant monumental statues, ...

, off the coast of mainland

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

Description

Butterflyfish have deep, laterally flattened bodies, a slightly upturned snout, uninterrupted dorsal fins and unforked, broadly wedge-shaped tail fins with flat ends. ''Chaetodon litus'' has a rectangular outline and is silvery-grey with white-edged scales. The maximum length is long. The dorsal fin has 13 spines and 23 to 25 soft rays while the anal fin has 3 spines and 19 or 20 soft rays.

Distribution and habitat

The Easter Island butterflyfish is native to the waters around Easter Island and is found nowhere else. Its preferred habitat is on reefs and among volcanic boulders heavily clad in

brown algae Brown algae (: alga) are a large group of multicellular algae comprising the class (biology), class Phaeophyceae. They include many seaweeds located in colder waters of the Northern Hemisphere. Brown algae are the major seaweeds of the temperate ...

at depths down to about . Juvenile fish are sometimes found among corals in rock pools.

Biology

Juvenile Easter Island butterflyfish have been observed to act as cleaner fish, picking

parasites Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

off the skin of larger fish. During the breeding season, male and female adult fish form pair bonds. The Easter Island butterflyfish is a bottom feeding fish. Examination of its stomach contents have shown that it feeds on polychaete worms,

shrimp A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchi ...

s, fish eggs and

barnacle Barnacles are arthropods of the subclass (taxonomy), subclass Cirripedia in the subphylum Crustacean, Crustacea. They are related to crabs and lobsters, with similar Nauplius (larva), nauplius larvae. Barnacles are exclusively marine invertebra ...

s, and fragments of the black

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

'' Amphimedon'' sp. were also found. This was unexpected as butterfly fish are not known to feed on sponges, however the explanation may be that the sponge was ingested in error when the fish was feeding on the barnacles which had become entangled in the sponge.

Status

At one time this fish was listed as " Vulnerable" by the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

in their

Red List of Threatened Species The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological spe ...

but in 2010, this was changed to being of "

Least Concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

". The reason given for this change was that, although its range was very limited, this fish was quite common within that range and did not face any significant threats. A small number of fish were collected for the

reef aquarium A reef aquarium or reef tank is a marine aquarium that prominently displays live corals and other marine invertebrates as well as fish that play a role in maintaining the tropical coral reef environment. A reef aquarium requires appropriately i ...

trade but the number was not believed to reduce the population to any great extent.

References

{{Taxonbar, from=Q304691 Easter Island butterflyfish Fish of Chile Fish of the Pacific Ocean Fauna of Easter Island Easter Island butterflyfish Taxonomy articles created by Polbot Endemic fauna of Chile