What types of sea urchins are poisonous?

Answered by Phillip Nicastro

Well, let me tell you about sea urchins and their venom. I’ve had a few encounters with these spiky creatures during my snorkeling adventures, so I can definitely give you some firsthand information.

Firstly, it’s important to note that not all sea urchins are poisonous. In fact, the majority of sea urchins are harmless and pose no threat to humans. However, there are certain types of sea urchins that do contain venom, and it’s best to steer clear of them if you come across one.

One group of venomous sea urchins is the long-spined ones. These include the Diadema and Echinothrix genii. Their spines are much longer compared to other sea urchins, and they are capable of injecting venom into anyone who steps on them or comes into contact with their spines. Trust me, you don’t want to experience the pain and discomfort that comes with a venomous sea urchin sting.

Another group of venomous sea urchins is the short-spined variety. This includes the Araeosoma, Asthenosoma, and Phormosoma genii. Though their spines may be shorter, they are still capable of delivering a venomous sting. So, it’s best to avoid these sea urchins as well.

Now, if you really want to talk about the most venomous sea urchin out there, then we have to mention the flower sea urchin, Toxopneustes pileolus. This little guy is notorious for being the most venomous sea urchin. Its venom is potent and can cause severe pain, muscle weakness, nausea, and even paralysis in some cases. Needless to say, you definitely want to stay away from this particular sea urchin if you come across it.

To summarize, the sea urchins known to be poisonous are the long-spined Diadema and Echinothrix genii, the short-spined Araeosoma, Asthenosoma, and Phormosoma genii, and the highly venomous flower sea urchin, Toxopneustes pileolus. It’s always important to exercise caution when swimming or snorkeling in areas where these sea urchins are known to inhabit. Trust me, you don’t want to end up with a painful sting from one of these creatures.