Kwajalein Surgeonfish (Acanthuridae)

Surgeonfish, or tangs, are among the most common fish on Kwajalein reefs. Most graze algae from the reef or sand, but some are primarily plankton eaters. All are characterized by a spine or sharp blade (hence the common name surgeonfish) near the caudal peduncle, the narrow part of the body just in front of the tail. This can be used to spine or slice anyone who handles them carelessly, and in some cases the spine is apparently venomous. A number of species are similar in size (commonly to around 10cm or so) and mostly black in color, and it seems we did not get photos of several of them. Species we have not photographed but which have been reported from the Marshall Islands are listed below the thumbnails with links to Fishbase.

Acanthurus achilles

Acanthurus blochii

Acanthurus guttatus

Acanthurus lineatus

Acanthurus mata

Acanthurus nigricans

Acanthurus nigricauda

Acanthurus nigroris

Acanthurus olivaceus

Acanthurus olivaceus juvenile

Acanthurus pyroferus

Acanthurus pyroferus juvenile

Acanthurus pyroferus juvenile

Acanthurus pyroferus juvenile

Acanthurus pyroferus juvenile

Acanthurus thompsoni

Acanthurus triostegus

Ctenochaetus binotatus

Ctenochaetus cyanocheilus

Ctenochaetus cyanocheilus juvenile

Ctenochaetus hawaiiensis

Ctenochaetus striatus

Ctenochaetus striatus

Naso annulatus

Naso annulatus juvenile

Naso brevirostris

Naso hexacanthus

Naso lituratus

Naso minor

Naso thynnoides

Naso unicornis

Naso vlamingi

Paracanthurus hepatus

Zebrasoma flavescens

Zebrasoma scopas

Zebrasoma scopas juvenile

Zebrasoma velifer

Zebrasoma velifer juvenile

Calico tang

Calico tang

various unidentified juveniles

Other surgeonfish species that have been reported from the Marshall Islands and listed in the checklist in Myers (1999) include (links are to Fishbase):

Acanthurus auranticavus Randall, 1956
Acanthurus maculiceps
(Ahl, 1923)
Acanthurus nigrofuscus (Forsskål, 1775)
Acanthurus xanthopterus Valenciennes, 1835
Ctenochaetus marginatus (Valenciennes, 1835)
Ctenochaetus tominiensis Randall, 1955
Naso caesius Randall & Bell, 1992
Naso brachycentron (Valenciennes, 1835)
Naso lopezi Herre, 1927
Naso tuberosus Lacepède, 1801


Myers, R. F. 1999. Micronesian Reef Fishes. Coral Graphics, Guam. 330pp.

Randall, J.E., R.F. Myers, M.N. Trevor, S.R. Johnson, J.L. Johnson, S. Yoshii & B.D. Greene. 2005. Ninety-one new records of fishes from the Marshall Islands. Aqua9(3):115-132.

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