This dreadful parasitic isopod lives in the mouths of fish, eating their blood and replacing their tongues. While we've already featured some really terrifying aquatic species, such as the Atlantic wolffish and the sardonic fringehead, the tongue-eating louse may be the creepiest of them ever. The tongue-eating louse, Cymothoa exigua, is an isopod (a kind of animal that … [Read more...] about These Eerie Little Creatures Live Within Fish’s Mouths, Replacing Their Tongues