It appears the Candiru has no attraction to urine, it hunts visually. It rarely, but occasionally, enters human orifices... probably less often than many insects. It can be up to 16 inches long. Hard to fit in many orifices.
"In 1836 Eduard Poeppig documented a statement by a local physician in Pará, known only as Dr. Lacerda, who offered an eyewitness account of a case where a candiru had entered a human orifice. However, it was lodged in a native woman's vagina, rather than a male urethra. He relates that the fish was extracted after external and internal application of the juice from a Xagua plant (believed to be a name for Genipa americana)"
"In 1891, naturalist Paul Le Cointe provides a rare first-hand account of a candiru entering a human body, and like Lacerda's account, it involved the fish being lodged in the vaginal canal, not the urethra. Le Cointe actually removed the fish himself, by pushing it forward to disengage the spines, turning it around and removing it head-first.[12]"
And, last but not least, the only male account of a supposed case:
"According to Samad, the patient claimed "the fish had darted out of the water, up the urine stream, and into his urethra." While this is the most popularly known legendary trait of the candiru, according to Spotte it has been known conclusively to be a myth for more than a century, as it is impossible because of simple fluid physics.[18]
The documentation and specimen provided indicate a fish that was 133.5 mm in length and had a head with a diameter of 11.5 mm. This would have required significant force to pry the urethra open to this extent. The candiru has no appendages or other apparatus that would have been necessary to accomplish this, and if it were leaping out of the water as the patient claimed, it would not have had sufficient leverage to force its way inside.[19]
Samad's paper claims the fish must have been attracted by the urine.[14] This belief about the fish has been held for centuries, but was discredited in 2001.[8] While this was merely speculation on Samad's part based on the prevailing scientific knowledge at the time, it somewhat erodes the patient's story by eliminating the motivation for the fish to have attacked him in the first place.
Samad claimed the fish had "chewed" its way through the ventral wall of the urethra into the patient's scrotum. Spotte notes that the candiru does not possess the right teeth or strong enough dentition to have been capable of this.[20]
Samad claimed he had to snip the candiru's grasping spikes off in order to extract it, yet the specimen provided had all its spikes intact.[19]
The cystoscopy video depicts traveling into a tubular space (presumed to be the patient's urethra) containing the fish's carcass and then pulling it out backwards through the urethral opening,[17] something that would have been almost impossible with the fish's spikes intact.[21]
When subsequently interviewed, Spotte stated that even if a person were to urinate while "submerged in a stream where candiru live", the odds of that person being attacked by candiru are "(a)bout the same as being struck by lightning while simultaneously being eaten by a shark." [22]"
@inferiorego: Good to hear you're doing okay. I had an epileptic seizure when I was a baby, very scary stuff. Hopefully you're okay in the future too.
We all appreciate you and the work you and Tony and Corey put in. You guys seriously make my day twice a week with what you do for a living. You touch so many lives! I have listened for nearly 2 years now. Thank you, again!
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