The stone fish s lifestyle makes this, the most venomous fish in the world, particularly dangerous to unwary humans. Lying on the seabed, looking exactly like an encrusted rock, it waits for small fish and shrimps to swim by and then, with lightning speed, opens its mouth and sucks them in. The whole ambush has been timed at just 0.015 seconds. Each stone fish spine is encased in a sheath containing bulging venom glands. Downward pressure on the spine causes the sheath to be pushed back, the venom from the pressurised glands shooting forcefully up grooves on the surface of the spine into the deepest part of the wound.
Victims become frantic with pain which lasts for hours.
Temporary paralysis, shock and even death may result. Stone fish may be found from exposed sand and mud in tidal inlets to depths of 40m. Also, take care when turning over rocks . Because they are barbed they can cause serious gashes and in about two-thirds of species they are also venomous. The spines are capable of penetrating wet suits and shoe leather and have been known to kill people unlucky enough to have been stabbed in the chest.