So there you are, swimming in the Amazon River in the heartland of Brazil, a smile on your face and a song in your heart. Birds call and monkeys chatter in the trees. Look at you! You're swimming in the Amazon! How awesome is that?

[You]: So awesome.

Damn straight. You're not even worried about piranhas. Piranhas are wimps, and you're awesome. Water snakes don't even faze you, you just punch them in the face. But listen. Do you hear that silence in the water? Do you see that nothing swimming around you in the empty river? If you do, then it's already too late.

[You]: Oh shit.

You've just encountered the candiru, you sad, sorry soul. It's a skinny, six-inch-long fish. It's translucent, so chances are you won't even see it in the water. It's been attracted by the chemicals your body is naturally exuding into the river, as that's how it tracks its normal prey, which is larger fishes.

[You]: A smaller fish preys on a larger fish?

That's the least of your worries right now, but yes. The candiru tracks fishes via chemicals and, taking advantage of its skinny profile, swims dart-like into the gills of a larger fish. The candiru jams itself in as far as it can go and extends backward-pointing spikes from its head, embedding itself inside the larger fish like an arrow. It will then feed on soft tissue and blood inside the larger fish's gills. When the candiru is satisfied, its spikes will relax and allow the candiru to swim away.

[You]: Good thing I'm not a fish.

Oh, you're cute. The candiru doesn't care. Your chemicals smell delicious, and he's come in to take a bite. But he won't bite you on the outside. He's looking for your gills.

[You]: Wait ...

The candiru will find an opening in your body and squeeze itself inside. In some cases, the opening it finds will be your urethra.

[You]: I'm not listening, la la la la --

The candiru will jam itself into your urethra, as far up as it can get, and then it will extend its spikes, lodging itself up in there by catching its sharp head-needles in your weak inner flesh. It will then begin to feed.

[You]: NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO--

Remember, the candiru is six inches long. Right now you should be looking down and imagining what it would feel like to have six inches of apocalypse devil fish jammed up your urethra, lodged so firmly with its spikes that even if you could get ahold of it and pull, you would only destroy your body and your mind by trying to yank it out.

[You]: --OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO--

But wait, there's more! Six inches is what a typical candiru reaches, but there are recorded cases of this fish reaching lengths of up to 16 inches. That's right, bitches. There are now 16 inches of fish stuck in your pee hole. Maybe it would leave half a foot or so dangling on the outside, just to make it impossible for you to forget the horror you are undergoing.

[You]: --OOOOOOOOOOOOOOO!

Are you okay?

[You]: No!

That's good. The fish is impossible to remove by conventional methods, and must be extracted via surgery. It may even be necessary, in the case of a man, to amputate. Yes, you know what I'm talking about.

[You]:

However, there has actually only been one officially documented case of a candiru attacking a human in this manner. It is theorized that this is because the candiru usually causes its victim to die from an overload of terror before he or she can get anywhere near a hospital.

Anecdotal accounts stretch back into the mid-1800s, but only in 1997 was there a recorded case. Surgery was required to remove the fish from the man's urethra. He told doctors that he had been urinating while standing nearly waist-deep in the river when the fish attacked him. It was hypothesized that the candiru was attracted to urea, as its natural prey also emits this chemical, but tests showed that this was not the case. The candiru appears to simply be attracted to body chemicals in general.

Animals, everybody. Animals are awesome.

Nate holds a Doctorate in Classical Bullshit, and teaches at a university so prestigious you've never even heard of it. But he still puts his pants on one leg at a time.