The blacknosed butterflyfish or barberfish (''Johnrandallia nigrirostris'') (from the

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Cana ...

names, ''El Barbero'' or ''Mariposa Barbero'', "the

barber A barber is a person whose occupation is mainly to cut, dress, groom, style and shave men's and boys' hair or beards. A barber's place of work is known as a "barbershop" or a "barber's". Barbershops are also places of social interaction and publi ...

" or "butterfly barber"), is a species of fish in the family Chaetodontidae, the butterfly fishes. It is found in the

East Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

, specifically around the Galápagos Islands and in the Sea of Cortez, and it sometimes acts as a

cleaner fish Cleaner fish are fish that show a specialist feeding strategy by providing a service to other species, referred to as clients, by removing dead skin, ectoparasites, and infected tissue from the surface or gill chambers. This example of cleaning ...

. It is the only member of the genus ''Johnrandallia'', named after the

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

John E. Randall, but in the past it was commonly placed in ''

Chaetodon ''Chaetodon'' is a tropical fish genus in the family Chaetodontidae. Like their relatives, they are known as "butterflyfish". This genus is by far the largest among the Chaetodontidae, with about 90 living species included here, though most migh ...

''.

Description

This species has a silvery-yellow, compressed body, and grows to . It is marked with black bands along the base of its dorsal fin, and on its snout and forehead. It has a small protractile mouth with a black, burglar-like mask around its eyes. ''Johnrandallia nigrirostris'' has brush-like teeth. It is superficially similar to '' Prognathodes carlhubbsi'' and '' P. falcifer'', which also are native to the East Pacific.

Distribution

''Johnrandallia nigrirostris'' is found in the

Eastern Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

from the

Gulf of California The Gulf of California ( es, Golfo de California), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Bermejo''), is a marginal sea of the Pacific Ocean that separates the Baja Ca ...

Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...

, including the

Cocos Island Cocos Island ( es, Isla del Coco) is an island in the Pacific Ocean administered by Costa Rica, approximately southwest of the Costa Rican mainland. It constitutes the 11th of the 13 districts of Puntarenas Canton of the Province of Puntarenas ...

Malpelo Island Malpelo is a small oceanic island in the eastern Pacific Ocean, located about west of the Colombian mainland with a military post manned by the Colombian Armed Forces. It consists of a sheer and barren rock with three high peaks, the highest ...

and the

Galápagos Islands The Galápagos Islands (Spanish: , , ) are an archipelago of volcanic islands. They are distributed on each side of the equator in the Pacific Ocean, surrounding the centre of the Western Hemisphere, and are part of the Republic of Ecuador ...

. It has also been recorded in

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

.Hooker, Y. (1990). ''Primer registro de johnrandallia nigrirostris, Gill 1862, en el Perú.'' Boletín de Lima 68: 69-71

Habitat

This species lives at depths ranging from near the surface to . It inhabits

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Co ...

s and rocky areas.

Behaviour

''Johnrandallia nigrirostris'' aggregates in small groups. It is highly active during the day, during which time it feeds. At night, it shelters near to the reef's surface. This species is a kind of

. It will remain at cleaning stations where infested fishes come to have various

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s and other

ectoparasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

s removed.

Diet

This species feeds on crustaceans,

molluscs Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant taxon, extant species of molluscs are recognized. The number of fossil sp ...

, and

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

Taxonomy and etymology

''Johnrandallia nigrirostris'' was first formally described as ''Sarothrodus nigrirostris'' in 1862 by the

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

Theodore Nicholas Gill (1837–1914) with the type locality given as

Cape San Lucas Cabo San Lucas (, "Saint Luke Cape"), or simply just Cabo, is a resort city at the southern tip of the Baja California Peninsula, in the Mexican state of Baja California Sur. As at the 2020 Census, the population of the city was 202,694 inhabitan ...

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

. In 1974 the

Romanian Romanian may refer to: *anything of, from, or related to the country and nation of Romania **Romanians, an ethnic group **Romanian language, a Romance language ***Romanian dialects, variants of the Romanian language **Romanian cuisine, traditional ...

ichthyologist Teodor T. Nalbant (1933–2011) placed it in the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus ''Johnrandallia'', named in honour of the American ichthyologist John E. Randall (1924-2020).

References

External links

* {{Taxonbar, from=Q807844 blacknosed butterflyfish Fish of the Gulf of California Fish of Mexican Pacific coast Western Central American coastal fauna Galápagos Islands coastal fauna Taxa named by Teodor T. Nalbant Fish described in 1974 Monotypic fish genera Monotypic marine fish genera Monotypic ray-finned fish genera