The fish have elongated dorsal fin spines and enlarged pectoral fins, and each species has a particular pattern of zebra like stripes.
A person punctured by one of the sharp spines will immediately feel strong pain. Rapid swelling of the affected body area develops along with the possibility of making movement of limbs very difficult. Lion-fish stings can cause nausea, breathing difficulties, paralysis, convulsions and collapse. Even death may occur in exceptional circumstances. Most people survive in spite of the great pain. The venom in the spines remains active for
days, so even discarded spines should be treated with caution. It may take several months for a full recovery and if the sting is left untreated, gangrene may develop.