Saltwater fish are the most beautiful fish in the world. They range from the majestic marlin to the funny-looking flounder, and the goliath grouper to the tiny blenny, and just about everything in between.
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The elusive hagfish is a master at hiding in holes and crevices, but its main defense is its ability to release a noxious, suffocating and sometimes poisonous slime when attacked.
By Mark Mancini
The showy lionfish is a stunning beauty. But this invasive species, which was released into the wild in the 1980s, is wreaking havoc on delicate reef ecosystems worldwide.
By Wendy Bowman
Most species of the rarely seen anglerfish live up to a mile beneath the ocean, where the females lure prey with a head-dangling hook appendage and permanently fuse with male suitors. It doesn't get much stranger than that.
By Katie Carman
The swordfish's nose might look crazy weird, but these gladiators of the sea are perfectly outfitted for ocean battle.
Humuhumunukunukuapua'a, the colorful little fish with the craaaaazy long name, is Hawaii's state fish, but it wasn't always.
The blobfish is actually pretty average looking in its normal habitat, but becomes a blob when it transitions from the pressure at depth to the water's surface.