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The Largest and the Smallest Fish

This is the top ten of the largest and heaviest fish! 72% of the earth’s surface is covered with water, and the deepest spot at the bottom of the sea can be found at a depth of 36,200 feet (11,034 meters) in the Mariana Trench in the Pacific Ocean.

This means there is plenty of space for the scaled inhabitants of this planet in the broad expanse of the ocean. Indeed, the ocean is such a many-faceted habitat that more than 32,500 species of fish have evolved there. This brings us to the question: Which are the largest fish that are living in the sea? Which are the smallest?

The Biggest and Heaviest Fish of the World

When asked for the largest fish in the ocean, people often hurriedly name the blue whale – but this is a mammal and not a fish! The whale shark is the largest fish – although you could mistake it for a whale because of its misleading name. Yet it is a shark and is called whale shark because it can reach the size of a whale.


The Heaviest Fish

Heaviest cartilaginous fish Whale shark 15-20 tons
Heaviest ray Pacific manta M. birostris 3 tons
Heaviest bony fish Ocean sunfish 2 tons
Heaviest sturgeon Beluga 1.476 tons
Heaviest carp Giant barb 661 lbs (300 kg)
Heaviest catfish Mekong giant catfish 645 lbs (293 kg)
Heaviest eel Conger 242 lbs (110 kg)
Heaviest angler Monkfish 110 lbs (50 kg)

The Longest Fish

Longest Fish Whale shark 41.5 feet (12.65 meters)
Longest bony fish Oarfish 36 feet (11 meters)
Longest predacious fish White shark 19.6 feet (6 meters)
Longest ray Giant manta M. birostris 16.4-29.5 feet (5-9 meters)
Longest eel Slender giant moray S. sathete 13.1 feet (4 meters)
Longest carp Giant barb 9.8 feet (3 meters)
Longest blowfish Giant triggerfish 29.5 inches (75 cm)
Longest goldfish Goldfish of Joris Gijsbers 18.6 inches (47.4 cm)
Longest seahorse H. abdominalis and H. bleekeri 13.7 inches (35 cm)

The Smallest Fish

Smallest predacious fish Dwarf lanternshark 5.9-7.8 inches (15-20 cm)
Smallest seahorse Denise’s pygmy seahorse 0.5 inches (1.35 cm)
Smallest blowfish Dwarf blowfish 0.8 inches (22 mm)
Smallest carp Paedocypris progenetica 0.3 inches (7.9 mm)
Smallest fish Angler P. spiniceps 0.2 inches (6.2 mm)

Oarfish Oarfish - Photo: LT DeeDee Van Wormer, U.S. Navy [Public domain], via Wikimedia Commons

Funny Fish Records

• The Fish That Can Do the Most Tricks

Dogs are able to do a lot of cool tricks (“roll”, “play dead” etc.). But fish? They are not generally known to be very good at performing stunts. Yet, Dean Poermleau’s fantail goldfish “Albert Einstein” (USA, 2005) shows what the slippery little friends are capable of. It could eat out of the palm of somebody’s hand, swim through a ring, swim through a tunnel, swim through under a stick and play soccer (!).

• The Fish With The Most Eyes

The deep sea fish Bathylychnops exilis does not have two eyes like most animals, but four. The additional pair of eyes focuses on the ground and probably helps the fish to detect threats.

• The Fish With the Longest Teeth

We are not talking of the white shark’s set of teeth. It has an incredible number of large teeth, but in relation to its body size, the deep-sea viperfish Chauliodus sloani has got the largest teeth (Guinness Book of World Records, 2011). They are so long that they even hang over the jaw when the mouth is closed. Its head is not bigger than 0.7 inches (2 cm), but its teeth are longer than 0.4 inches (1 cm).

Ocean Sunfish Ocean Sunfish - Photo: Mohamed AlQubaisi/Shutterstock



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