Candiru

Candiru (English and Portuguese) or candirú (Spanish), also known as cañero, toothpick fish, or vampire fish, are a number of genera of parasitic freshwater catfish in the family Trichomycteridae; all are native to the Amazon River. Although some candiru species have been known to grow to a size of 40 centimetres (16 in) in length, others are considerably smaller. These smaller species are known for an alleged tendency to invade and parasitise the human urethra; however, despite ethnological reports dating back to the late 19th century, the first documented case of the removal of a candiru from a human urethra did not occur until 1997, and even that incident has remained a matter of controversy.