Nothing, except for this fish, appropriately named the elephantnose fish (Gnathonemus petersii) for its peculiar, elongated spout. The fish is widespread in the flowing waters of West Africa and hunts insect larva at dawn and dusk. Its nose is actually a sensitive extension of its mouth, that it uses for self-defense, communication, navigation, and finding worms and insects to eat. This organ is covered in electroreceptors, as is much of the rest of its body. The elephantnose uses a weak electric field, which it generates with specialized cells called electrocytes, which evolved from muscle cells, to find food, to navigate in dark or turbid waters, and to find a mate. The elephantnose fish live to about 6 to 10 years. ...

Lingcods are sometimes found with amazing, edible blue flesh. A bile pigment called biliverdin seems to be the cause, but exactly how it gets into the flesh of the fish remains a mystery.

A living, swimming ghost fish has been seen live for the first time ever.

The fish, part of the family Aphyonidae, was caught on camera during an ongoing National Oceanic and Atmospheric Administration (NOAA) exploration by the ship Okeanos Explorer. The exploration centers on the deep ocean at Mariana Trench Marine National Monument, a protected area spanning 95,216 square miles (246,608 square kilometers) east of the Philippines.

The secretive fish was swimming along a ridge 8,202 feet (2,500 meters) down, according to NOAA. The animal is about 4 inches (10 centimeters) long, with translucent, scale-less skin and eerie, colorless eyes. No fish in the family Aphyonidae has ever been seen alive before.

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Penguins may lack teeth, but they have backward facing spines in their throats that grip and guide fish down.

The angry-looking deep sea angler fish has a right to be cranky. It is quite possibly the ugliest animal on the planet, and it lives in what is easily Earth's most inhospitable habitat: the lonely, lightless bottom of the sea.

There are more than 200 species of anglerfish, most of which live in the murky depths of the Atlantic and Antarctic oceans, up to a mile below the surface, although some live in shallow, tropical environments. Generally dark gray to dark brown in color, they have huge heads and enormous crescent-shaped mouths filled with sharp, translucent teeth. Some angler fish can be quite large, reaching 3.3 feet (1 meter) in length. Most however are significantly smaller, often less than a foot.

Their mouths are so big and their bo ...

The new species is member of the arapaima genus, which contains some of the world’s biggest freshwater fish that breathe air and weigh up to 200kg. Found in the central Amazon of Brazil, the new fish has been named Arapaima leptosoma and is the first new species of arapaima described since 1847.

Why do these fish look like they’re spouting puffs of magic dust out of their mouths? The tiny crustaceans (1 millimetre-long crustacean called an ostracod) that these transparent fish try to eat light them up, causing the fish to be at risk of predation themselves, so they spit them out!

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