Parasite or Devoted Father?

LuAnne alerted me to this tiny fishie. What you're looking at is the smallest vertebrate on the planet. Actually, you're probably looking at the female, which is the larger of this pairing. Pairing, you say? Yes - take a look at that thing stuck on the back of the fish. That is the male fish.

This is a classic example of sexual parasitism (oh, so many joke opportunities here!). With this fish (Photocorynus spiniceps, found in peat swamps in Southeast Asia), the male (measuring at only 6.2 mm) attaches itself to the female. This is a permanent union which allows the male to partake of the nutrients supplied by the female, which in turn lets him focus on his job; nearly all of his body cavity is filled with his testes. He is a one-purpose fish: breeding. She benefits by having him at hand for baby time.

Is this an example of parasitism, or is it an example of a truly dedicated father? You be the judge.

Thanks for the article, LuAnne.

UPDATE: There is a lot of junk on the web, or at least a lot of less-than-factual stuff. Unfortunately, this site can too often be found in the same pile o' doo-doo. Our preeminent ichtyologist, Rasmus, has pointed out two flaws with this post - I suggest you read his comment. But thanks for the encouragement, Swintah, and for helping me save some face.

Photo courtesy: Nutmeg's StumbleUpon