Is this the grossest parasite? - Niko Zlotnik

One night in 2013, a man in Northern Ireland was shocked to discover something bizarre protruding from the mouth of the sea bass he was preparing for dinner.

Peering closer, he came face-to-face with none other than the infamous “tongue biter,” also known as the tongue-eating louse.

This species, Cymothoa exigua, is one of nearly 400 belonging to a family of fish parasites called cymothoids.

They’re crustaceans, and more specifically, isopods, like pill bugs.

Some latch onto their host's head, others suck blood from fish gills, and still others burrow into fish flesh and form sac-like membranes around themselves.

Clearly, there are many delightful ways to be a cymothoid, but Cymothoa exigua and others go specifically for fish tongues— or at least what pass as tongues among fish.