6 Fascinating Facts About Fish Tongues You Never Knew
Ever bitten into fried cod tongues and thought, “Wait… do fish even have tongues?” Same here.
Turns out they do — but it's nothing like the pink, wiggly thing in your mouth.
Here's the short version, plus a few facts that are honestly kind of unsettling. (Yes, there's a parasite involved. We'll get there.)
So, do fish have tongues?
Yes — but let's set expectations.
What fish have is called a basihyal: a bony structure sitting on the floor of the mouth.
It looks a bit like a tongue. But it's not muscular, it doesn't taste anything, and it definitely doesn't lick.
Instead, the basihyal mostly protects important blood vessels — like the ventral aorta — and in some species helps nudge food or water through the mouth.
“A fish tongue is less “taste and chew” and more “bony floor tile with a job to do.””
But do every fish get one?
Do all fish have them?
Most do — but it varies from species to species.
And here's the wild part: some fish lose their basihyal entirely.
Not to age. Not to injury. To a parasite that replaces it. More on that horror show in a minute.
Wait — what about “cod tongues” on menus?
Here's the plot twist that started this whole rabbit hole (fish tank?) for me.
Those “cod tongues” aren't tongues at all.
They're a tasty muscle from the back of the cod's neck — not the basihyal. So the dish that sparked my curiosity wasn't even the thing I was curious about.
Can fish have teeth on their tongues?
They can — and plenty do.
Certain species have small teeth on the basihyal, usually pointing backward.
These aren't for chewing. They grip prey and push it toward the throat.
Think less “chew toy” and more “conveyor belt with spikes.”
Okay, now for the genuinely creepy part.
Let's talk about that tongue-eating parasite
Meet Cymothoa exigua, better known as the tongue-eating louse. It's a parasitic isopod, and its life plan is deeply unsettling.
Can you guess?
What does this parasite actually do to a fish's tongue?
Gross? Absolutely. Fascinating? Also absolutely.
Here's the strange biology: these parasites usually start life as males, then switch to females once they attach.
The good news for the fish — sort of — is that the louse doesn't usually kill its host. But it can make eating and breathing harder, so the fish gets by, just not as comfortably.
Quick answers to common questions
Yes — like other fish, goldfish have a basihyal. Peek into their mouth and you might spot it.
They do, and not just in their mouths. Many fish have taste buds on their lips, fins, and even skin. Catfish are the extreme example, with over 100,000 taste buds, including on those whisker-like barbels.
Yes. Depending on the species, teeth can appear on the jaws, throat, lips — even the tongue. Carnivores tend to have sharp, gripping teeth, while herbivores have flatter teeth for grinding.
Yep. Sea stars, urchins, crustaceans, and even some frogs (like pipidae frogs) have no tongue whatsoever. Nature is delightfully weird.
Sviatoslav Oleksiv founded The Pets and Love in 2019. A lifelong pet owner and Rhodesian Ridgeback enthusiast, he writes and edits our guides to help fellow pet parents give their animals the best care.
Every guide follows our editorial standards. This article is for informational purposes only and is not a substitute for professional advice — always consult a licensed veterinarian about your pet's health.