Scorpionfish, Lionfish, and Stonefish – The Toxic Trio for 2025

Apr 24, 2025 | 3 minute read Comments
16
Reading Time: 3 minutes

When people think of Scorpionfish, they usually think of a single species, and rightfully so. Only, they aren’t just a single fish, they’re an entire family of hundreds of species. This is one cool family, mind you. Amongst these fish, you’ll find some of the most venomous and unusual looking creatures on the planet. These are the toxic trio, and today, you’ll learn everything about them.

A close-up of a Weedy Scorpionfish in dark water, on a the sea bottom

Meet the Family

First of all, let’s get all that family confusion out of the way. Scorpionfish, Lionfish, and Stonefish all belong to the same family of fish – Scorpaenidae. Doesn’t exactly roll off the tongue, does it? So instead of saying “Scor-pae-ni-dae” every time, people went with Scorpionfish for the entire family. 

The Scorpaenidae is a large family, counting several hundred distinct species. Most of them are very recognizable (if you can spot them) and highly venomous!

Where Scorpionfish, Lionfish, and Stonefish diverge is in the subfamilies (genera). True Scorpionfish belong to the Scorpaena subfamily. Lionfish come from the Pterois genus, and Stonefish count themselves among the Synanceja.

As you’d imagine, people just call these the Scorpionfish, Lionfish, and Stonefish subfamilies, and then add a descriptive common name for an individual species. That’s how you get names like “Flasher Scorpionfish” and “Red Lionfish.”

Scorpionfish vs. Lionfish vs. Stonefish

Alright, that’s enough names, let’s compare these fish!

Scorpionfish – Scorpaena

Fish from the Scorpaena subfamily are mostly sedentary prey-stalkers. These carnivores got their name from the many toxic spikes and spines across their bodies. The venom from these contains powerful neurotoxins that can be extremely painful, and even deadly. And yes, that goes for humans too. 

A close-up of a Red Scorpionfish hiding between rocks on sea bottom
A Red Scorpionfish

Scorpions come in a wide variety of colors, sometimes to scare other fish away, and other times to blend into their environment. They are fantastic at camouflage, and sometimes even use biofluorescence (glowing with a different color) to blend into their environment! Scorpionfish like temperate and tropical waters, and you can mostly find them in the Indo-Pacific Ocean.

Common species include:

  • Red Scorpionfish 
  • Flasher Scorpionfish 
  • Papuan Scorpionfish

Lionfish – Pterois

Similarly to Scorpaena, Lionfish boast a number of poisonous spikes. However, the spikes on these guys are often elaborately colored and spread out – think underwater peacock. Lionfish don’t use their colors for show and seduction, however, but rather to stun any fish (or human) that would endanger them.

A close-up of a Lionfish in an aquarium, with its fins spread wide

Another thing that sets Lionfish apart is their insatiable appetite. Unlike Scorpaena, Lionfish don’t wait for their food to approach them, but rather move out and hunt on their own.

In recent years, these fish have decimated countless reefs in Florida and the Caribbean. Worse yet, they have almost zero natural predators. This is why they are now considered one of the most dangerous invasive species in the Atlantic. 

The good news is, they taste good, so if you want to save the reefs, get yourself a Lionfish dinner.

Common species include:

  • Red Lionfish 
  • Clearfin Lionfish
  • Spotfin Lionfish 
  • Luna Lionfish 
  • Devil Lionfish

Stonefish – Synanceja

Stonefish might not have the visual appeal of Scorpionfish and Lionfish, but they make up for it with their sting. These guys are the most poisonous fish in the sea, and can even be fatal to humans. Like Scorpionfish, their feeding strategy is to sit and wait for their prey. Due to their appearance, you’d really have a tough time discerning them from a rock.

A close-up of a Stonefish at the bottom of an aquarium
You’ve got to admit, he’s all charm

Stonefish spines are much more venomous than those of Lionfish and Scorpionfish. They are thicker and more prominent, too. Additionally, Stonefish boast a sharp specialized spike, a lachrymal saber, as an extra defensive weapon. You can find Stonefish in the coastal regions of the Indo-Pacific.

Common species include:

  • Dwarf Stonefish 
  • Reef Stonefish
  • Estuarine Stonefish

Now that you know everything about this big toxic trio, how’d you like to see a Flasher Scorpionfish go against a Lionfish?

What do you think about Scorpionfish? Which of these fish is your favorite? Have you ever encountered one before? Let us know in the comments below.

Author profile picture

Sean is a former optometrist who quit his day job to write about fishing. He calls himself a lucky angler because his favorite fish, the Mahi Mahi, can be found almost anywhere – though he’s lost more of them than he’s willing to admit. Nowadays, Sean works as a product marketer but can't help writing a few words about fish every now and then.

Comments (16)
Leave a comment
NameRequired
Your comment Required

Joshua IV

Jun 22, 2024

I take my kids snorkeling often here in Puerto Rico. I came across a stonefish a couple days ago. I was not aware of their poisonous stings. I was having a hard time telling if it was a dead fish or what it was. I nudged it twice with the tip of my fin. It would not swim away. Glad I didn’t get stung.

Leave a reply
NameRequired
Your comment Required

John Orr

Jan 6, 2023

Whilst working on a military base in Tabuk north west Saudi Arabia we’d go scuba diving almost every weekend, usually to Dhuba or Al Wedj on the Red sea and occaisonally to Haql on the Gulf of Aqaba, it was unheard of to not wear foot protection whilst crossing reefs to get into deep water as we’d been warned ad nauseum about the dangers of Stone and Scorpion fish, we almost always had medical staff on the trips with us who carried anti venom in their medical kits but most advised that they’d prefer anyone stung should use hot water immersion rather than anti venom as in some cases it could cause cardiac problems, so we always had a large pot of water on the camp stove every time we dived or even snorkled. a friend had the bad luck to stand on a stonefish whilst mapping a dive plan on the reef at Haql and he was wearing diving booty’s at the time but two spines pierced the half inch thick rubber sole, I’ve seen people badly injured in many ways including gunshot wounds and explosion injuries but I’ve never seen anyone in so much pain as he was suffering but once the medics got the water to the correct temperature (I believe it was 40 to 45 degrees centigrade or 110 fahrenheit) his relief was almost instantaneous. a few months later whilst in Aqaba (Jordan) on a weekend break we were on the beach behind the Holiday inn which is part of the Gulf of Aqaba, some local lads were playing with a ball in the water with no foot protection on when we heard screaming from one of the lads but thought it was just horseplay but realised it was something serious as the screaming continued and got louder, before we reached him in the water the screaming stopped,the lad was dead and as we got him to the beach we could see his foot was still impaled on a large stonefish, we were informed about a week later that the massive invenomation the lad suffered brought on cardiac arrest.

Leave a reply
NameRequired
Your comment Required

Amy Thomson

Oct 1, 2022

I’ve just returned from our Honeymoon in Mauritius. We were on a day trip and one of the last stops was a pure white sand beach where we had a BBQ prepared. I went for a swim to cool off after lunch, where I was assured I wouldn’t need my water shoes.
I stepped on a stone fish. Initially I thought I’d cut my foot on a piece of coral as it was just a sting. But once I’d got back on the beach (literally 30 seconds) the pain was so intense and my foot doubled in size. I can only describe the pain as the worst I’ve ever felt and a cross between burning and electricity. The speed boat crew who took us out assured me it was just coral and wasn’t poison. And I’d be ok. I knew that wasn’t the case as I’ve never had pain like it and the swelling was instant. We had to get back on the speed boat and go to the last stop which was a waterfall. Then get back to the dock and wait for the rest of the boats to arrive before our transfer took us back to the hotel. These few hours I barely remeber because of the pain. When we got back to the hotel they sent the drs and immediately sent me to hospital.
I had to undergo multiple x rays as they were initially treating me for an urchin. Once they’d determined there was no spines in my skin so couldn’t be an urchin. They sent for another dr. The dr said instantly it was a stone fish and I was taken to the ward, given anti venom, strong painkillers, fluids and an extra hot water bottle to put my foot on which helped ease the pain. Later that night they had to make a local lesion to get any local venom out. After that i had a course of antibiotics, anti inflammatory, painkiller and stayed on my drip until lunch time the next day and had another anti venom. I feel super lucky as the dr said only one spine got me. I’m back in the UK now and have seen it here. They’re happy I’m healing well and am able to walk properly. All in all I got off lightly but wouldn’t reccomened it to anyone!!

Leave a reply
NameRequired
Your comment Required

  • Rhys

    Oct 3, 2022

    Hi Amy,

    Thanks for taking the time to share your story with us. It sounds like one heck of an ordeal! I’m glad to hear you’re on the mend, but it definitely serves as a reminder as to how dangerous these creatures can be.

    Take care,

    Leave a reply
    NameRequired
    Your comment Required

View all replies