This 2006 video says about itself:
From the BBC:
Would the candiru fish really eat your genitals?
The story is that the fish swims up a stream of urine into a man’s penis, then eats it from the inside. But is there any truth to it?
By Josh Gabbatiss
4 January 2016
Of all the denizens of the Amazon basin, there is none more feared than the tiny fish known as the candiru. Since coming to the attention of science in the early 19th century, this creature has occupied the very darkest recesses of the popular imagination.
The reason for this is the candiru’s supposed habit of entering the human penis, lodging itself in place with sharp barbs, and feasting on it from the inside – a horror story that is enough to keep your legs firmly crossed for days.
This tale has been told everywhere: from documentaries on the BBC and Animal Planet to Grey’s Anatomy; from William S. Burroughs‘ Naked Lunch to Chuck Palahniuk‘s Fight Club; and invariably it serves as shorthand for the worst thing that could possibly happen to a human being. Internet forums abound with references to the fish, as well as grisly embellishments concerning its activities – laying eggs in bladders and suchlike.
So far, so disgusting. But it is not at all clear that any of this is true. …
The thing is, despite all the graphic depictions of genital mutilation, not one of these men ever witnessed a candiru attack. There are dozens of reports from the 19th and early 20th centuries of candiru behaviour, and every one relies exclusively on hearsay.
As WR Allen, a renowned Amazonian ichthyologist, put it: “I was toId of numerous cases of the candirus entering the urethra, but they were always some distance downstream, and when I arrived downstream I was told of many such cases upstream”.
So has the candiru been miscast as a penis-chomping villain?