Clupeiformes › Clupeidae
Atlantic herring
Up to 45 cm long
Few fish on Earth are more common than this one.
Field Guide · Chapter 15 of 29
Ocean fish
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Perciformes › Scombridae
Yellowfin tuna
Over 180 kg
Unlike most fish, tuna like this one are warm-blooded.
Perciformes › Xiphiidae
Swordfish
Up to 4.55 m long
The spearing picture of the swordfish is based on little evidence. It more likely slashes.
Perciformes › Coryphaenidae
Mahi-mahi
Can swim 92.6 km/h
Mature males grow a forehead that often sticks well above the body.
Pleuronectiformes › Pleuronectidae
Atlantic halibut
Up to 4.7 m long
The largest flatfish in the world, it grows up to 4.7 m long.
Scorpaeniformes › Synanceiidae
Reef stonefish
40 cm at most
It is the most venomous fish in the world.
Tetraodontiformes › Diodontidae
Spot-fin porcupinefish
Up to 91 cm
Its scales have become long spines that lie flat along its body.
Perciformes › Labridae
Humphead wrasse
Up to 229 cm long
Some of these fish turn into males, and the timing of that change is not yet known.
Perciformes › Labridae
Bluestreak cleaner wrasse
Sex change in 24 hours
A larger female can change sex and take over a territory.
Perciformes › Zanclidae
Moorish idol
Up to 23 cm long
Males and females release eggs and sperm into the water, and the eggs drift off on the current.
Perciformes › Acanthuridae
Blue tang
Up to 38 cm long
Spawning shows as a change from dark blue to pale blue.
Syngnathiformes › Syngnathidae
Leafy seadragon
Can reach 50 cm
Its leafy fringes are not for swimming. They only serve as camouflage.
Anguilliformes › Muraenidae
Mediterranean moray
Up to 1.5 m long
Off Sardinia, this eel was documented hunting in a team with a grouper.
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