Are there any creatures that are wholly inedible for humans to eat?

[Rysdad]

@Johnny_L.A

Silver fish are generally safe to eat.

Barracuda are mostly silvery…with spots, or with other species, stripes.

And the old saying that Smeghead was referring to is, “Shorter than your arm will do you no harm.”

I ain’t about to try it, though.

[salinqmind]

I live near a highly polluted lake that a factory used as a convenient dumping ground for decades. Efforts have been made to clean it up. Sport fishing is allowed, though eating the fish is STRONGLY discouraged. (I wouldn’t even want to put my hand in that water!). I suppose eating fish tainted with mercury and a laundry list of deadly chemicals, not to mention such fish swimming in sewage laden water, would kill you later, if not sooner.

[Johnny_L.A]

@Rysdad

Barracuda are mostly silvery…with spots, or with other species, stripes.

That’s why I said ‘generally’. I’m sure there are non-poisonous colourful fish. The Field Manual probably used it as a guideline to prevent down pilots from chowing down on triggerfish, and thought it unlikely he’d catch a large barracuda.

I meant to ask if anyone else had heard that (implied by my saying that the FM was the only place I’d heard it).

[DrDeth]

I am pretty sure that the Echinoderms more or less follow what the OP wants. There just isn’t enough stuff there besides the calcite portions that would make it edible for humans. There are a few other critters along those lines also, I can’t see humans eating Bryozoa either.

[Mk_VII]

The Galah bird found in Australia. Totally inedible. They used to say you had to boil it up with an old boot 'til the boot was tender, then throw the Galah away and eat the boot.

[Isamu]

@RealityChuck

It was trivial to do it. When I was growing up, we had blowfish as a matter of course. I even cleaned a few myself. I was certainly under 12 when I did it and the only training I had was watching my grandfather do it. No big deal. No one ever mentioned that they were potentially poisonous.

IIRC, you would make a cut just behind the fin to cut off the tail and peel it out of the skin and throw the rest away. That kept away from any of the poisonous organs; you’d only eat the tail muscle.

Now these were the Atlantic Ocean variety, which may have been different than the ones the Japanese eat (though I believe they still have the poison). Also, we always cooked blowfish, which could have broken down the poison (fugu is served raw).

Finally, looking at a video of a Japanese chef preparing the fugu, he’s doing it completely differently, in a way where it is much more likely that the poison gets on the meat if there’s a mistake (but where you get more meat from the fish).

Yeah, they use more parts here than just the tail meat. But most fatalities are from people cooking it for themselves at home. My wife’s family cook it at home and I eat it, usually tetchiri style (boiled), but the big difference is we don’t cut up the fish ourselves, but instead buy the raw pieces from a professional. I’m pretty sure both skin and some blood are still attached to parts of the raw pieces when we pick them up.

[gonzomax]

Does anybody eat skunk?

[FlyingRat]

@drachillix

Jellyfish

Jellyfish-related deaths are rare, but the sting they inflict is extremely painful. The Portuguese man-of-war resembles a large pink or purple balloon floating on the sea. It has poisonous tentacles hanging up to 12 metres below its body. The huge tentacles are actually colonies of stinging cells. Most known deaths from jellyfish are attributed to the man-of-war. Other jellyfish can inflict very painful stings as well. Avoid the long tentacles of any jellyfish, even those washed up on the beach and apparently dead.

Certain species of jellyfish in the order Rhizostomae are edible by humans-- these aren’t the dangerous stinging ones, though. This page gives some background and recipes on jellyfish consumption in Asia. I’ve had it, and I like it-- it’s got no flavor, but a nice, “crunchy” texture, and is good with some soy sauce and Japanese plum paste.

[HorseloverFat]

Finally, looking at a video of a Japanese chef preparing the fugu, he’s doing it completely differently

I read somewhere that these chefs are cutting it in a way that allows some poison to get through because customers want to feel numb or high from the poison. Not sure how accurate that is, but it may explain his technique.

[Colibri]

@DrDeth

I am pretty sure that the Echinoderms more or less follow what the OP wants. There just isn’t enough stuff there besides the calcite portions that would make it edible for humans. There are a few other critters along those lines also, I can’t see humans eating Bryozoa either.

Regarding echinoderms, some are certainly edible. Sea urchin gonads are popular as sushi, and sea cucumbers are also extensively harvested for food for the Asian market.

It’s true that a number of invertebrates don’t have much in the way of “flesh” to eat, but they could probably be made into soup. The tissue isn’t poisonous, which I think is what the OP is most interested in.