Vampire Catfish

Sometimes I learn things in my Biology class that give me the heebie-jeebies. My biology professor has been to the Amazon and confirms this fish is real. From the website http://www.buzzle.com/editorials/2-29-2004-51087.asp

Candirú or Canero (Vandellia cirrhosa) is a freshwater fish belonging to the Catfish group. The species grows only to being one to two inches in length and four to six millimeters wide. It is shaped like an eel and is almost completely transparent, making it almost impossible to see in the water. A fast, powerful swimmer, the fish is smooth and slimy, with sharp teeth and backward-pointing spines on its gill. The Candiru is primarily found in the Amazon and Oranoco rivers and has a reputation among the natives as the most feared fish in its waters. The reason that the Candiru is most feared by humans is because it is the only vertebrate known to parasitize humans! The fish is said to be addicted to the taste and smell of human urine. Candirus parasitize humans, when they are skinny-dipping while urinating in the water. The candiru tastes the urine stream and follows it back to the human. It then swims up the urethra and lodges itself somewhere in the urinary tract with its spines. Blood is drawn, and the candiru gorges itself on the blood and body tissue, its body sometimes expanding due to the amount of blood consumed. Once inside it would eat away the mucous membranes and tissues until hemorrhage would kill it or the host. It was also said that even if one caught the fish by the tail, once in the urethra it could not be pulled out because it would spread itself like an umbrella. The Candiru can attack both men and women.

I decided not to post the medical pictures of these being removed from a mans urethra.