Tongue-eating. Louse. There's not much to like about those words. In fact, one gets the impression that it'll be something utterly disgusting, like, I don't know... a louse that eats tongues. Something horrible like that. Yeh.The Tongue-eating Louse is a parasite from Californian waters, but it's far more abominable than your average blood sucking intestine botherer.It starts when a youngster attaches itself to the gills of a rather attractive and entirely innocent Spotted Rose Snapper . It grows and becomes male. Maybe it's feasting on fish gill mucus? That would be disgusting if I didn't occasionally take cod liver oil.Anyway, at some point it matures into a female, probably all embarrassed about those silly things it used to do when it was a young male. Then it probably mates somehow . I wonder if it mates once as a male and then once as a female? Who knows? (I really don't know if anyone knows...) Who cares? (I kinda do) We got Tongue-eating to do! And it doesn't involve teenagers kissing with inappropriate passion, either.The Tongue-eating Louse moves into the Snapper's mouth, places itself on the tongue and... doesn't actually eat it. Instead, it grabs hold and drinks blood from it. In fact, this isopod drinks so much blood that the tongue atrophies away, starved of all nutrients.But the Tongue-eating Louse is a kind hearted parasite. It wouldn't do a fish such a wrong and leave it pining for the memory of its tongue. Not after all the blood and mucus it so kindly provided whether it wanted to or not.Instead, the friendly louse grabs hold of the stump left in the Snapper's mouth and serves as a whole new tongue. A tongue with eyes and 7 pairs of legs. At 3 to 4 cm in length, the Tongue-eating Louse is just about the right size and even allows the Snapper to use her like an actual tongue. Sure, the Snapper won't be able to kiss with inappropriate passion ever again, but at least it won't starve to death. Or whatever happens when a fish doesn't have a tongue.And neither will the louse. In return for not leaving her host in life-endangering devastation and grief over a lost organ, she feeds on yet more mucus with a bit of blood for dessert. For ever and ever. Until death do them part.Sort of cute in a way.