Synanceia verrucosa is a fish species known as the reef stonefish or simply stonefish. It is a carnivorous ray-finned fish with venomous spines. It lives on reef bottoms camouflaged as a rock. It is the most venomous known fish in the world. It can be lethal to humans. This stonefish lives primarily above the Tropic of Capricorn. It is the most widespread species in the stonefish family, and is known from shallow tropical marine waters in the Pacific and Indian Oceans from the Red Sea to the Great Barrier Reef.
This stonefish is usually brown or gray, and it may have areas of yellow, orange or red. This species reaches 30 to 40 centimeters long; a specimen of 51 centimeters has been recorded. This fish lives in coral reefs. It may settle on and around rocks and plants, or rest on the seabed. It eats mostly small fish, shrimp and other crustaceans.