Head to head
Stonefish vs Red Lionfish
The stonefish and the lionfish are cousins in the scorpionfish family, and both carry venomous spines, but they advertise themselves in completely opposite ways. One hides; the other shows off.
| Stonefish | Red Lionfish | |
|---|---|---|
| Family | Scorpaenidae (Synanceia) | Scorpaenidae (Pterois) |
| Strategy | Camouflage; lies still and hidden | Warning display; hovers in the open |
| Venom potency | The most potent of any fish | Painful but rarely dangerous |
| Spines | 13 short, stout dorsal spines | 13 long dorsal spines, plus pelvic and anal |
| How people get stung | Standing on a hidden fish | Handling, netting, or cornering the fish |
| Hunting | Ambush; strikes in ~15 milliseconds | Stalks and corners prey with its fins |
| First aid | Hot water, then antivenom and hospital | Hot water; hospital if severe |
| Invasive threat | No | Yes, severe in the western Atlantic |
Stonefish vs Lionfish: common questions
Are stonefish and lionfish related?
Yes, closely. Both are in the scorpionfish family, Scorpaenidae, a group of mostly bottom-living marine fish characterised by venomous fin spines, large heads, and, in many species, elaborate skin flaps and camouflage. The stonefish is in the genus Synanceia and the lionfish in the genus Pterois. They share the basic venom apparatus, a pair of venom glands running along grooves in each stiff spine, with the venom injected by the pressure of the spine being pushed into flesh. What differs is everything about how they live and, critically, how toxic that venom is.
Which sting is worse?
The stonefish, without question. A lionfish sting is one of the more painful things that can happen to a diver or aquarist, with throbbing pain spreading up the limb, swelling, and sometimes nausea and headache, but it typically settles over hours to a day or two and is very rarely dangerous to a healthy person. A stonefish sting is in a different category: immediate, overwhelming pain often described as the worst imaginable, rapid swelling, tissue death around the wound, and, with multiple spines or no treatment, the risk of breathing and heart problems and, historically, death. Stonefish antivenom exists and is widely stocked across the Indo-Pacific. For both, the immediate first aid is to immerse the area in water as hot as can be tolerated, which breaks down part of the venom.
Why is the lionfish such a problem in the Atlantic?
Lionfish are native to the Indo-Pacific, but individuals released or escaped from aquariums off Florida in the late 20th century founded a population that has since spread through the western Atlantic, the Caribbean, and the Gulf of Mexico. In this new range they have no natural predators or parasites that recognise them, they breed year-round, and they eat huge numbers of small native reef fish, including the juveniles of ecologically and commercially important species. Reef managers now run lionfish culling derbies and promote lionfish as a food fish, since the flesh is excellent once the spines are removed. The stonefish, being a sit-still ambusher tied to its home patch, has never spread this way.