Fish
Oarfish
World's longest bony fish
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There are 16 animals that start with the letter O, including the Oarfish, Ocean Sunfish, Oceanic Whitetip Shark, and more. See photos, facts, and full guides for each.
Fish
World's longest bony fish
Fish
The heaviest bony fish
Fish
Critically Endangered lord of the open ocean
Mammal
The spotted cat of the Americas
Invertebrate
The shape-shifting genius of the sea
Mammal
The forest giraffe of the Congo
Mammal
Africa's adaptable monkey
Amphibian
Blind cave salamander of European karst
Mammal
North America's only marsupial
Mammal
The great ape of the Southeast Asian rainforest
Mammal
The ocean's top predator
Insect
The Southeast Asian insect that mimics a flower to lure and ambush prey
Amphibian
The green toad with a warning-red belly
Bird
The fish-hunting raptor of coasts and lakes
Bird
The largest and fastest bird on land
Mammal
The playful, water-loving member of the weasel family
Animals beginning with O include Oarfish, Ocean Sunfish, Oceanic Whitetip Shark, Ocelot, Octopus, and 11 more.
Our guide currently covers 16 animals whose names start with O.