46 photos - 22 species


There are 2 subfamilies, 6 genera and over 80 species.

Surgeonfish get their name from their sharp scalpel-like blades,

which are used for defense.

Most have one on the left and one on the right between

the end of the body and the beginning of the tail.

The nose doctors have two on the left and two on the right.

Most reach a size of between 30 and 40 cm, depending on the species,

with the smallest species reaching 12 cm and the largest up to 1 m in length.

Larva of a surgeonfish

The females of the surgeonfish species lay thousands of eggs,

which float freely in the water on an oil ball.

After 5 - 6 days, during which they feed on their yolk sac,

they switch to plankton and eat the small crustaceans

and juvenile fish floating in the water.

After 2 - 3 months they return to the reefs,

where they find enough food and hiding places.

They are scaleless and transparent.

Photo 1 Johnny: Bonaire Caribbean

Acanthurus bahianus

Ocean surgeon or Ocean surgeonfish

Maximum length: 40 cm

Depth: 5 - 25 m

Their coloration can change from blue-grey to dark brown,

as well as fading or darkening considerably.

Their eyes have a radial pattern.

Their tail root may have a pale (see photo) transverse band.

It is a reef dweller that grazes on algae in shoals together with blue surgeonfish

and the similar-looking striped surgeonfish.

Not shy, but swims away slowly when approached. 

Photos 1 - 2 Johnny: Bonaire Caribbean

Photos 3 - 4 Astrid: Bonaire Caribbean

Acanthurus chirurgus

Doctorfish tang or Doctorfish

Maximum length: 30 cm

Depth: 5 - 25 m

Body has 12 horizontal stripes, which are sometimes very faint.

Photo shows dark color form without band on the base of the caudal fin.

Photos 1 - 2 Johnny: Bonaire Caribbean

Acanthurus coeruleus

Atlantic blue tang, Blue barber, Blue doctor, Blue doctorfish, Blue tang, Blue tang surgeonfish, Yellow barber or Yellow doctorfish


Maximum length: 35 cm

Depth: 3 - 25 m

Coloration can change from light blue to dark purple or fade and become darker.

The dorsal and anal fins have bright blue edges.

Occasionally seen on their own, but mostly in large shoals grazing on algae.

Not shy, rather indifferent.

 Photos 1 + 3 - 5 Astrid: Bonaire Caribbean

Photo 2 Johnny: Bonaire Caribbean

Acanthurus gahhm

Black surgeonfish, Monk surgeonfish or Lined surgeonfish

Maximum length: 40 cm

Depth: 1 - 40 m

The caudal fin of juveniles is rounded, that of adults sickle-shaped.

This species lives in groups or loose aggregations in open water

over gravel or sandy bottoms in lagoons and outer reefs.

Photos 1 - 2 Johnny: Hurghada Egypt

Acanthurus japonicus

Japan surgeonfish, White-faced surgeonfisch, Gold rim tang,

Powder brown tang or White-nose surgeonfish

Maximum length: 14 cm

Depth: 3 - 20 m

Their dorsal and anal fins have a yellow baseline, as well as a yellow horizontal stripe in the caudal fin.

The blade is yellow.

Prefers outer reefs.

Grazes filamentous algae from hard substrates.

Photo 1 Johnny: Bangka Island North Sulawesi

Acanthurus leucosternon

Blue surgeonfish, Powder blue tang or Powder-blue surgeonfish

Maximum length: 18 cm

Depth: 5 - 35 m

Sometimes in large schools in the Maldivian reefs.

Photo 1 Johnny: Embudu Maldives

Acanthurus lineatus

Lined surgeonfish, Blue banded surgeonfish, Blue-lined surgeonfish, Clown surgeonfish, Pyjama tang, Striped surgeonfish or

Zebra surgeonfish

Maximum length: 38 cm

Depth: 0.5 - 20 m

Found in the Indian Ocean and the Pacific.

Photo 1 Johnny: Embudu Maldives

Acanthurus mata

Pale surgeonfish, Blue-lined surgeonfish, Mata surgeonfish, Striped surgeonfish, Tailring surgeon, White-tail lanced or Yellowmask surgeonfish

Maximum length: 50 cm

Depth: 3 - 30 m

Plankton eaters, form small shoals in the middle of the water.

Photo 1 Johnny: Embudu Maldives

Acanthurus nigricans

Goldrim surgeonfish, Velvet surgeon, Whitecheek surgeonfish,

Yellow-banded surgeonfish or Yellowrimmed surgeonfish

Maximum length: 15 cm

Depth: 70 m

Usually found in small to large groups on outer reef crests.

Almost identical to Acanthus japonicus (see above)

but nigricans has a small spot under the eye.

Photos 1 - 2 Johnny: Bangka Island North Sulawesi

Acanthurus pyroferus

Chocolate surgeonfish, Mimic surgeonfish, Orange-gilled surgeonfish, Pacific mimic surgeon or Yellowspot surgeon

Maximum length: 20 cm

Depth: 10 - 40 m

Solitary in shallow coastal waters where they graze algae from rocks or sand.

Photo 1 Johnny: Moalboal Philippines

Photo 2 Johnny: Bali Indonesia

Acanthurus sohal

Sohal surgeonfish or Sohal tang

Maximum length: 40 cm

Depth: 0.5 - 10 m

Narrow, black and white stripes and black middle fins with light blue edges.

Very aggressive, vehemently defends a small territory even against divers and snorkelers.

Not shy.

Photo 1 Johnny: El Qesir Egypt

Photo 2 Astrid: Embudu Maldives

Ctenochaetus striatus

Striated surgeonfish, Lined bristletooth, Fine-lined Bristletooth or Striped bristletooth

Maximum length: 26 cm

Depth: 1 - 30 m

Dark brown body with fine, light-colored stripes and yellow pectoral fins.

It has orange spots on its head.

At home on reef tops, outer reefs and in lagoons.

Likes to live in schools with other surgeonfish.

Eats diatoms and blue-green algae.

Photo 1 Johnny: El Qesir Egypt

Photo 2 Johnny: Hurghada Egypt

Naso brachycentron

Humpback unicornfish

Maximum length: 90 cm

Depth: 2 - 30 m

Striking long frontal hump,

reminiscent of a unicorn ( English name Humpback unicornfish ).

Like all surgeonfish species,

it has a laterally flattened body and razor-sharp spines

at the base of the tail.

Photo 1 Johnny: Bangka Island North Sulawesi

Naso brevirostris

Short-nosed unicornfish, Spotted unicornfish, Brown unicornfish,

Lined unicornfish, Longnose surgeonfish, Palefin unicornfish,

Paletale unicornfish, Shorthorned unicornfish or Shortnouted unicornfish

Maximum length: 60 cm

Depth: 3 - 50 m

Live in small groups along the drop - offs.

Photos 1 + 2 Johnny: Hurghada Egypt

Naso elegans

Elegant unicornfish, Blonde naso tang, Indian orange-spine unicorn, Lipstick surgeonfish, Lipstick tang, Orangespine unicornfish or Smoothheaded unicornfish

Maximum length: 45 cm without the long threads at the tail end

Depth: 1 - 90 m

Although nose doctor, " without horn ", but with 2 orange scalps

which actually only the nose doctors have,

all other doctors normally only have one on each side.

Eats mainly brown algae.

Photos 1 - 3 Johnny: Hurghada Egypt

Naso hexacanthus

Sleek unicornfish, Blue-tail unicorn, Thorpe's unicornfish,

Blacktongue unicornfish or 'Opelu kala

Maximum length: 75 cm

Depth: 6 - 100 m

Without horn.

This species can change its color very quickly to light blue during courtship.

Hunts large zooplankton a few meters from the reef.

Photo 1 Johnny: Hurghada Egypt

Photo 2 Astrid: Hurghada Egypt

Naso unicornis

Bluespine unicornfish or Short-nose unicornfish

Maximum length: 70 cm

Depth: 1 - 35 m

Color: grey to olive.

Blue bone blades on the caudal peduncle.

Likes to travel in groups, feeding on rough leaf algae.

Photos 1 - 2 Johnny: Hurghada Egypt

Naso vlamingii

Bignose unicornfish, Scibbled unicornfish, Vlaming's unicornfish or Zebra unicornfish

Maximum length: 40 cm

Depth: 2 - 50 m

During courtship, or when preening, this species displays bold blue stripes and spots.

Likes to shade divers and play in their bubbles.

Photos 1 - 2 Johnny: Embudu Maldives

Paracanthurus hepatus

Regal tang, Palette surgeonfish, Blue tang, Royal blue tang,

Hippo tang, Blue hippo tang, Flagtail surgeonfish,

Pacific regal blue tang or Blue surgeonfish

Maximum length: 30 cm

Depth: 10 - 40 m

Palmetto surgeonfish are widespread in the Indo-Pacific.

They prefer to live in outer reefs, as juveniles in shoals, as adults in pairs or singly.

In contrast to other surgeonfish, which are mostly growth-feeders,

the palette surgeonfish hunts for plankton in open water.

It can be easily recognized by its laterally compressed, egg-shaped body.

It feeds mainly on algae.

Like all surgeonfish, it has a scalpel-like spine that is very sharp

and serves as a defense against enemies when erected.

Photo 1 Johnny: Luxembourg ( Aquarium )

Zebrasoma desjardinii

Red sea sailfin tang, Desjardin's sailfin tang, Indian sailfin tang or Indian sailfin surgeonfish

Maximum length: 40 cm

Depth: 1 - 30 m

As you can see here in the photo, it raises its large dorsal and anal fins during imposition.

Photos 1 - 2 Johnny: El Qesir Egypt

Photo 3 Johnny: Hurghgada Egypt

Zebrasoma scopas

Brown tang, Twotone tang, Scops tang or Brush-tail tang


Maximum length: 17 cm

Depth: 1 - 60 m

The body is brownish and colored with a fine net pattern.

Photo 1 shows a juvenile animal.

Similar to the Indian sailfin doctor, it raises its dorsal and anal fins when showing off.

Photo 1 Johnny: Bangka Island North Sulawesi

Photo 2 Johnny: Embudu Maldives

Zebrasoma xanthurum

Purple tang or Yellowti tang

Maximum length: 22 cm

Depth: 0.5 - 22 m

Blue body with yellow tail and red spots on the head.

Found on upper reef slopes and coral-rich patch reefs.

Grazes filamentous algae from rubble, rocks and dead corals.

Not very shy

Photos 1 - 2 Johnny: Hurghada Egypt