The Stonefish (Synanecja horrida) is is arguably of the ugliest fish in the sea. This fish gets its name from its stone-like appearance. This excellent disguise allows it to blend in with the background as it waits for its prey. If a small fish wanders too close, it disappears instantly in the powerful jaws. In addition to its gruesome looks, the stonefish has sharp, venomous spines that contain enough venom to kill a man. They are one of the most venomous fish in the world. They grow to a maximum size of 2 feet (60 centimeters).