Devil scorpionfish: Sinister style with venom

Our next candidate of the group of ambush predators presented in “They got the look” is the devil scorpionfish a.k.a. false stonefish presenting its sinister style with venom. In general, we don’t think it is very nice to call somebody or something false. This fish is pretty real and has the venom to prove it. There is also a scientific reason why the common name devil scorpionfish suits it better (see classification below). However, let’s take a closer look at the creature first.

Juvenile devil scorpionfish (*Scorpaenopsis diabolus*) already shwing the small skin flap growing over the eye and the protruding hump on the back.

Not just black and white

Typically, the devil scorpionfish (Scorpaenopsis diabolus) lies on the sea floor or on a coral head, waiting for the night to begin. Often it covers itself with sand and other debris to stay well hidden. In the picture above, the juvenile is of a darker colour with smoother skin, fully grown most of this species turn into some sort of drab shades (3rd picture). Nevertheless, there are exceptions with some individuals showing patches of pink, red and orange. Roughly every six weeks, devil scorpionfish undergo a change of skin to get rid of parasites and afterwards the colour is usually more vibrant again. The inner surface of the pectoral fins is brilliant yellow with orange with distinct dark spots.

The pronounced hump on the back is a distinguishing feature in comparison to stonefish as both of them have the same grim expression on the mouth. Another pointer is the eye of the devil scorpionfish the camouflage continues over its pupil. This flap of skin breaks up the outline of the eye, concealing the sinister creature even better while it sits and waits for prey.

Underwater close-up (crop) of the eye of an devil scorpionfish (Wakatobi, Indonesia) showing how the camouflage continues of this ambush predator continues into the eye.

Sinister style with venom

A devil scorpionfish can grow up to 30 cm and has twelve venomous spines down its back plus another three on the anal fin. It flashes its pectoral fins as a warning and would choose to move and give up its camouflage rather than relying on the venom. Like pretty much all marine creatures it will only attack if it is cornered and can not flee instead. If a careless diver just happens to kneel down on such a creature, it might neither get the chance to show off the warning display nor move in time. Only one of the reasons to always practise good buoyancy control and keep the hands of the reef.

The devil scorpionfish (*Scorpaenopsis diabolus*) has this forked skin flap growing over the pupil to conceal the outline of the eye, stonefish neither have that part of camouflage nor do they have to pronounced hump on the back.

Devil scorpionfish: Food, habitat and reproduction

They feed on small fishes, crustaceans and pretty much anything that unknowingly ventures too close to the devil – and fits into its mouth. As a true ambush predator (Ambush predators: They got the look) it just sucks its prey up and is not a very good swimmer. If need be, they hop away on their pectoral fins.

Devil Scorpionfish are widespread across the Indo-Pacific area as well as all the way along the East coast of Africa to the Red sea. Singly or in pairs, they are blending into their surroundings of coral, rock, rubble and weedy bottoms of reef flats, lagoons and seaward reefs.

“Devil Scorpionfish are oviparous with females producing eggs that when fertilized are released and float near the surface. Little else is known about their reproduction.”
Seaunseen: Devil Scorpionfish

Scientific classification

Common names vary, some call this creature a false stonefish. Looking at the scientific name reveals it is classified as a diabolic scorpion whereas stonefish belong to the family of Synanceiidae. To make it more confusing: There is also the genus of devilfish (Inimicus) part of the ambush predator crew. More to come!