In an ancient dance ritual performed by the Australian Aborigines, a man wades into the tide pools in search of fish. Suddenly he steps on something – a clay model of a stonefish with 13 wooden dorsal fins – and screams in pain. The dancer writhes on the ground in agony, and the ritual ends sadly with a death song.

The stonefish is the most venomous fish known. Lying on the seabed, looking exactly like an encrusted rock, it waits for small fish and shrimps to swim by. Then with lightening speed (just 0.015 seconds) the fish opens its mouth and sucks them in.

Stonefish reach up to about 15 inches (35 cm) in length and live in the Indo-Pacific region and northern Australian waters. This fish has 13 grooved spines sharp enough to puncture rubber, which it uses for pure defense against bottom-feeding sharks and rays. It has a spiny head with large pectoral fins, and it is bluntly built and covered with flaps of skin and wart-like bumps. To round out the camouflage, it is grayish-brown in color and blends in perfectly with the ocean floor.

The stonefish is only dangerous if stepped on or caught. The dorsal spines project from venom glands along the back, and venom is involuntarily expelled when pressure is placed on them. In fact, the victim is the one who injures himself. It takes a few weeks for the glands to regenerate and recharge.

Victims experience excruciating pain that lasts for hours and a tremendous swelling develops with the death of the tissues. Temporary paralysis, shock and even death may result. The severity of symptoms depends on the depth of penetration and the number of spines involved.

You can prevent injury by wearing thick-soled shoes and treading very lightly; spines have been known to pierce through a shoe. If you are stung by a stonefish, you can immerse the area in hot water. But for severe symptoms, which include excruciating pain, weakness and paralysis, and multiple punctures, the only real treatment is the administration of stonefish antivenin – and an intravenous narcotic analgesia for pain.