This is so awesomely disgustingly great I had to post it. There’s a louse that consumes a fish’s tongue and replaces it with itself. Cymothoa exigua was discovered inside the mouth of a red snapper bought from a London market. The louse had grabbed ahold of the tongue and slowly eaten it away until only a stub was left. It then latched onto the stub and became the fish’s tongue — getting a free meal after having fed on the tongue artery while it ate away.

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