Next, there is the specimen. This food -related article is a stub. World Register of Marine Species. Other sources also suggest that other tribes in the area used various forms of protective coverings for their genitals while bathing, though it was also suggested that these were to prevent bites from piranha. The one that is generally thought to be the culprit is the 5cm-long Vandellia cirrhosa. 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 , and even that incident has remained a matter of controversy. Environmental Biology of Fishes.