Acanthuridae

Acanthuridae
Sohal surgeonfish, Acanthurus sohal
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Suborder:	Acanthuroidei
Family:	Acanthuridae
Genera
Acanthurus Ctenochaetus Naso (unicornfishes) Paracanthurus Prionurus Zebrasoma

Acanthuridae ("thorn tails") is the family of surgeonfishes, tangs, and unicornfishes. The family includes about 80 species in six genera, all of which are marine fish living in tropical seas, usually around coral reefs. Many of the species are brightly colored and popular for aquaria.

The distinctive characteristic of the family is the spines, one or more on either side of the tail, which are dangerously sharp. The dorsal, anal and caudal fins are large, extending for most of the length of the body. The small mouths have a single row of teeth used for grazing on algae.

Surgeonfishes sometimes feed as solitary individuals, but they also often travel and feed in schools. It has been suggested that feeding in schools is a mechanism for overwhelming the highly aggressive defense responses of small territorial damselfishes that vigorously guard small patches of algae on coral reefs.

Most species are relatively small and have a maximum length of 15–40 cm (6–16 in), but some members of the genus Acanthurus, some members of the genus Prionurus, and most members of the genus Naso can grow larger, with the whitemargin unicornfish (N. annulatus), the largest species in the family, reaching a length of up to a metre (3,3 ft). These fishes can grow quickly in aquariums so it is advisable to check the average growth size and suitability before adding to a marine aquarium.

Species

Achilles tang, Acanthurus achilles

Eyestripe surgeonfish, Acanthurus dussumieri

Powderblue surgeonfish, Acanthurus leucosternon

Doubleband surgeonfish, Acanthurus tennenti

Kole Tang, Ctenochaetus strigosus

Elongate unicornfish, Naso lopezi

Bluespine unicornfish, Naso unicornis

Red Sea sailfin tang, Zebrasoma desjardinii

Orangespot surgeonfish, Acanthurus olivaceus, is being cleaned by two Hawaiian cleaner wrasse, Labroides phthirophagus

Regal Tang, Paracanthurus hepatus in an aquarium

• Genus Acanthurus
  • Achilles tang, Acanthurus achilles Shaw, 1803.
  • Whitefin surgeonfish, Acanthurus albipectoralis Allen & Ayling, 1987.
  • Orange-socket surgeonfish, Acanthurus auranticavus Randall, 1956.
  • Ocean surgeon, Acanthurus bahianus Castelnau, 1855.
  • Black-spot surgeonfish, Acanthurus bariene Lesson, 1831.
  • Ringtail surgeonfish, Acanthurus blochii Valenciennes, 1835.
  • Doctorfish tang, Acanthurus chirurgus (Bloch, 1787).
  • Chronixis surgeonfish, Acanthurus chronixis Randall, 1960.
  • Atlantic Blue tang surgeonfish, Acanthurus coeruleus Bloch & Schneider, 1801.
  • Eyestripe surgeonfish, Acanthurus dussumieri Valenciennes, 1835.
  • Fowler's surgeonfish, Acanthurus fowleri de Beaufort, 1951.
  • Black surgeonfish, Acanthurus gahhm (Forsskål, 1775).
  • Finelined surgeonfish, Acanthurus grammoptilus Richardson, 1843.
  • Whitespotted surgeonfish, Acanthurus guttatus Forster, 1801.
  • Japan surgeonfish, Acanthurus japonicus (Schmidt, 1931).
  • Palelipped surgeonfish, Acanthurus leucocheilus Herre, 1927.
  • Whitebar surgeonfish, Acanthurus leucopareius (Jenkins, 1903).
  • Powderblue surgeonfish, Acanthurus leucosternon Bennett, 1833.
  • Lined surgeonfish, Acanthurus lineatus (Linnaeus, 1758).
  • White-freckled surgeonfish, Acanthurus maculiceps] (Ahl, 1923).
  • Elongate surgeonfish, Acanthurus mata (Cuvier, 1829).
  • Monrovia doctorfish, Acanthurus monroviae Steindachner, 1876.
  • Whitecheek surgeonfish, Acanthurus nigricans (Linnaeus, 1758).
  • Epaulette surgeonfish, Acanthurus nigricauda Duncker & Mohr, 1929.
  • Brown surgeonfish, Acanthurus nigrofuscus (Forsskål, 1775).
  • Bluelined surgeonfish, Acanthurus nigroris Valenciennes, 1835.
  • Bluelined surgeon, Acanthurus nubilus (Fowler & Bean, 1929).
  • Orangespot surgeonfish, Acanthurus olivaceus Bloch & Schneider, 1801.
  • Black-barred surgeonfish, Acanthurus polyzona (Bleeker, 1868).
  • Chocolate surgeonfish, Acanthurus pyroferus Kittlitz, 1834.
  • Gulf surgeonfish, Acanthurus randalli Briggs & Caldwell, 1957.
  • Acanthurus reversus Randall & Earle, 1999.
  • Sohal surgeonfish, Acanthurus sohal (Forsskål, 1775).
  • Doubleband surgeonfish, Acanthurus tennentii Günther, 1861.
  • Thompson's surgeonfish, Acanthurus thompsoni (Fowler, 1923).
  • Convict surgeonfish, Acanthurus triostegus (Linnaeus, 1758).
  • Indian Ocean mimic surgeonfish, Acanthurus tristis Randall, 1993.
  • Yellowfin surgeonfish, Acanthurus xanthopterus Valenciennes, 1835.
• Genus Ctenochaetus
  • Twospot surgeonfish, Ctenochaetus binotatus Randall, 1955.
  • Ctenochaetus cyanocheilus Randall & Clements, 2001.
  • Ctenochaetus flavicauda Fowler, 1938.
  • Ctenochaetus hawaiiensis
  • Striped-fin surgeonfish, Ctenochaetus marginatus (Valenciennes, 1835).
  • Striated surgeonfish, Ctenochaetus striatus (Quoy & Gaimard, 1825).
  • Kole Tang, Ctenochaetus strigosus (Bennett, 1828).
  • Tomini surgeonfish, Ctenochaetus tominiensis Randall, 1955.
  • Ctenochaetus truncatus Randall & Clements, 2001.
• Genus Naso
  • Whitemargin unicornfish, Naso annulatus (Quoy & Gaimard, 1825).
  • Humpback unicornfish, Naso brachycentron (Valenciennes, 1835).
  • Spotted unicornfish, Naso brevirostris (Cuvier, 1829).
  • Naso caeruleacauda Randall, 1994.
  • Gray unicornfish, Naso caesius Randall & Bell, 1992.
  • Elegant unicornfish, Naso elegans (Rüppell, 1829).
  • Horseface unicornfish, Naso fageni Morrow, 1954.
  • Sleek unicornfish, Naso hexacanthus (Bleeker, 1855).
  • Orangespine unicornfish, Naso lituratus (Forster, 1801).
  • Elongate unicornfish, Naso lopezi Herre, 1927.
  • Naso maculatus Randall & Struhsaker, 1981.
  • Squarenose unicornfish, Naso mcdadei Johnson, 2002.
  • Slender unicorn, Naso minor (Smith, 1966).
  • Naso reticulatus Randall, 2001.
  • Oneknife unicornfish, Naso thynnoides (Cuvier, 1829).
  • Bulbnose unicornfish, Naso tonganus (Valenciennes, 1835).
  • Humpnose unicornfish, Naso tuberosus Lacépède, 1801.
  • Bluespine unicornfish, Naso unicornis (Forsskål, 1775).
  • Bignose unicornfish, Naso vlamingii (Valenciennes, 1835).
• Genus Paracanthurus
  • Palette surgeonfish, Paracanthurus hepatus (Linnaeus, 1766).
• Genus Prionurus
  • Biafra doctorfish, Prionurus biafraensis (Blache & Rossignol, 1961).
  • Prionurus chrysurus Randall, 2001.
  • Razor surgeonfish, Prionurus laticlavius (Valenciennes, 1846).
  • Yellowspotted sawtail, Prionurus maculatus (Randall & Struhsaker, 1981).
  • Sixplate sawtail, Prionurus microlepidotus Lacépède, 1804.
  • Yellowtail surgeonfish, Prionurus punctatus Gill, 1862.
  • Scalpel sawtail, Prionurus scalprum Valenciennes, 1835.
• Genus Zebrasoma
  • Red Sea sailfin tang, Zebrasoma desjardinii (Bennett, 1836).
  • Yellow tang, Zebrasoma flavescens (Bennett, 1828).
  • Spotted tang, Zebrasoma gemmatum (Valenciennes, 1835).
  • Longnose surgeonfish, Zebrasoma rostratum (Günther, 1875).
  • Twotone tang, Zebrasoma scopas (Cuvier, 1829).
  • Sailfin tang, Zebrasoma veliferum (Bloch, 1795).
  • Purple tang, Zebrasoma xanthurum (Blyth, 1852).
  • Zebrasoma xanthurus

Timeline of genera

Etymology and taxonomic history

The name of the family is derived from the Greek words akantha and oura, which loosely translate to "thorn" and "tail", respectively. This refers to the distinguishing characteristic of the family, the "scalpel" found each member's caudal peduncle.

In the early 1900s, the family was called Hepatidae.

In the aquarium

Tangs are very sensitive to disease in the home aquarium. However if the tang is fed enough algae and the aquarium is properly maintained disease should not be a problem. It is usually necessary to quarantine the animals for a period before introducing them to the aquarium.

Adults range from 15–40 cm (6-15 in.) in length and most grow quickly even in aquariums. When considering a tang for an aquarium it is important to consider the size to which these fish can grow. Larger species such as the popular Pacific Blue tang surgeonfish (of Finding Nemo fame), Naso or lipstick tang, clown and sohal tangs can grow to 40 cm (15 in.) and require swimming room and hiding places.

Many also suggest adding aggressive tangs to the aquarium last as they are territorial and may fight and possibly kill other fish.

Tangs primarily graze on macroalgae, such as caulerpa and gracilias, although they have been observed in an aquarium setting to eat meat-based fish foods. A popular technique for aquarists, is to grow macroalgae in a sump or refugium. This technique not only is economically beneficial, but serves to promote enhanced water quality through nitrate absorption. The growth of the algae can then be controlled by feeding it to the tang.

References

• Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology 364: p.560. http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class. Retrieved 2011-05-19.