Isopods found in the most unusual places.

Yes you read that right.

Isopods are small marine crustaceans and not commonly a topic of blogs or household conversation.

Recently there has been a meme around the internet of an isopod on a fishes mouth. In fact, it was often presented as a guessing game and all sorts of guesses were baby fish, cleaner shrimp and all rather benevolent causes.

I knew this was not a baby fish. I didn't recognized the species initially, and the first thought that came to me was that those two were the undigested prey of the fish. But the marine biologist in me wasn't happy with the answer. Were they really the undigested prey of the fish? They looked nasty, with segmented body and evil little eyes. They have seven pairs of claws underneath their belly. SEVEN! What kind of animal that needs fourteen limbs?

So I dragged out the old Invertebrate Zoology text book for information for these animals, and ta-da! They were actually the parasitic crustacean called tongue-eating louse, Cymothoa exigua.

This animal enters fish through the gills, and attaches itself to the base of the fish's tongue. It suck the blood from the tongue, causing the tongue to slowly waste away-a condition called antropy. So it's basically eating away the fish's tongue. The louse will then attach itself to the muscle of the tongue, and the fish can use the parasite just like a normal tongue.

Image: threadless.com

The female is typically larger, and attaches itself on the tongue, while the smaller male usually attaches itself behind the female. The two creatures I found inside the fish, one of them was male and the other female.

Image: themanyfacesofspaces.com

Wikipedia says that the parasite is found mostly in the North and South American seas, until one was found in the United Kingdom in 2005, which means there are these parasites in the Atlantic as well.

Which brings me to another topic, ticks.  I hate them. Disgusting little creatures and they will be the subject of another blog entry. But these isopods remind me of tick on fish.  yeck.



info: http://www.dnr.sc.gov/marine/sertc/Isopod%20Crustaceans.pdf