Marine life  /  Surgeonfish & unicornfish
26 of 1316 species
Group

Surgeonfish & unicornfish

Grazers that keep algae off the reef, named for the hinged blade at the base of the tail. It folds into a groove and is used sideways with a flick of the body, against other fish rather than against divers.

Species
26
Depth
0–60 m
Rarity range
1 star of 5, found on most divesto 2 stars of 5, usually seen in a week
Night only
None
Can hurt a diver
8
Destinations
13

Many feed in roving shoals, and the reason is territory. A single surgeonfish cannot get into a damselfish's algal patch; forty of them can, because the damselfish cannot drive off all of them. A shoal crossing a reef at speed is usually doing exactly that.

The unicornfish carry a horn or a bump that grows with the fish and is present only in some species. Several also change colour within seconds, and a fish at a cleaning station often shows a paler pattern than the same fish a minute later.

The blade is sharp enough to cut, and a caught or handled surgeonfish will use it. In the water it is not a hazard.

26 species

Photographed first, then commonest

26 written up, none photographed yet

Every one has a page. They are shown as a list rather than as pictures because nothing has been photographed or logged for them yet, and a species with nothing behind it should not sit in front of one that has.

Where they are recorded

How many of the 26 carry a record at each destination. A species usually carries several, so these do not add up to 26.

Lembeh Strait 13 Anilao 13 Bali 13 Papua New Guinea 13 Dauin & Dumaguete 7 Islas Revillagigedo 6 Maldives 5 Red Sea 3 Florida 3 Bahamas 3 Cayman Islands 3 Galapagos Islands 1 Cocos Island 1

The other groups

Anemonefish 11 Angelfish 25 Batfish 3 Blennies 26 Butterflyfish 35 Cardinalfish 13 Damselfish 32 Dottybacks 5 Dragonets 5 Eels & garden eels 18 Flatfish 8 Frogfish & anglers 26 Goatfish 8 Gobies & dartfish 29 Groupers & anthias 42 Hawkfish 5 Jacks & open-water fish 29 Jawfish 4 Lizardfish & flatheads 10 Morays 26 Morwongs & trumpeters 4 Parrotfish 16 Pufferfish & boxfish 23 Rabbitfish 5 Scorpionfish & lionfish 47 Seahorses & pipefish 53 Shrimpgobies 17 Snappers, breams & sweetlips 39 Squirrelfish & soldierfish 9 Triggerfish & filefish 25 Trumpetfish & cornetfish 4 Wrasses 56 Other fish 46 Sharks & rays 63 Turtles, sea snakes & crocodiles 11 Marine mammals & birds 10 Cephalopods 36 Nudibranchs & sea slugs 137 Sea snails & shells 26 Shrimps 38 Mantis shrimps 5 Crabs 45 Hermit crabs 10 Lobsters & squat lobsters 13 Isopods & parasitic crustaceans 5 Amphipods 2 Sea stars 18 Brittle stars & basket stars 7 Feather stars 2 Sea urchins 23 Sea cucumbers 12 Worms 11 Flatworms 3 Jellyfish & stinging drifters 10 Anemones & zoanthids 12 Corals & sponges 29 Sea squirts 4 Blackwater & plankton 52 Other invertebrates 2

All 1316 species in one index, with filters for destination, rarity and hazard.

← Squirrelfish & soldierfish Triggerfish & filefish →