Johnrandallia Explained

The blacknosed butterflyfish or barberfish (Johnrandallia nigrirostris) (from the Spanish names, El Barbero or Mariposa Barbero, "the barber" or "butterfly barber"), is a species of fish in the family Chaetodontidae, the butterfly fishes. It is found in the East Pacific, specifically around the Galápagos Islands and in the Sea of Cortez, and it sometimes acts as a cleaner fish.[1] It is the only member of the genus Johnrandallia, named after the ichthyologist John E. Randall, but in the past it was commonly placed in Chaetodon.

Description

This species has a silvery-yellow, compressed body, and grows to 20.3cm (08inches). 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.[2]

Distribution

Johnrandallia nigrirostris is found in the Eastern Pacific from the Gulf of California to Panama, including the Cocos Island, Malpelo Island and the Galápagos Islands. It has also been recorded in Peru.[3]

Habitat

This species lives at depths ranging from near the surface to 40m (130feet). It inhabits coral reefs 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 cleaner fish. It will remain at cleaning stations where infested fishes come to have various crustaceans and other ectoparasites removed.

Diet

This species feeds on crustaceans, molluscs, and algae.

Taxonomy and etymology

Johnrandallia nigrirostris was first formally described as Sarothrodus nigrirostris in 1862 by the American ichthyologist Theodore Nicholas Gill (1837–1914) with the type locality given as Cape San Lucas, Baja California. In 1974 the Romanian ichthyologist Teodor T. Nalbant (1933–2011) placed it in the monotypic genus Johnrandallia, named in honour of the American ichthyologist John E. Randall (1924-2020).[4]

Notes and References

  1. Web site: SDNHM - Johnrandallia nigrirostris (Barberfish. Mariposa barbero) . 2011-05-11 . 2013-02-06 . https://web.archive.org/web/20130206072021/http://www.oceanoasis.org/fieldguide/john-nig.html . dead .
  2. Allen, G. R., and Robertson, R. (1994). Fishes of the Tropical Eastern Pacific.
  3. Hooker, Y. (1990). Primer registro de johnrandallia nigrirostris, Gill 1862, en el Perú. Boletín de Lima 68: 69-71
  4. Web site: Order ACANTHURIFORMES (part 1): Families LOBOTIDAE, POMACANTHIDAE, DREPANEIDAE and CHAETODONTIDAE . The ETYFish Project Fish Name Etymology Database . 26 November 2020 . 21 July 2020 . Christopher Scharpf . Kenneth J. Lazara . amp . Christopher Scharpf and Kenneth J. Lazara.