Asian pit vipers - from 2 to 5 ft. long, throughout Asia; reactions and mortality vary, but most bites cause tissue damage and mortality is generally low.
Australian brown snakes - 4 to 7 ft. long; very slow onset of cardiac or respiratory distress; moderate mortality, but because death can be sudden and unexpected, it is the most dangerous of the Australian snakes; antivenom.
Barba Amarilla or Fer-de-lance - up to 7 ft. long, from tropical Mexico to Brazil; severe tissue damage common; moderate mortality; antivenom.
Black mamba - up to 14 ft. long, fast-moving; S and C Africa; rapid onset of dizziness, difficulty breathing, erratic heart-beat; mortality high, nears 100% without antivenom.
Boomslang - under 6 ft. long, in African savannahs; rapid onset of nausea and dizziness, often followed by slight recovery and then sudden death from internal hemorrhaging; bites rare, mortality high; antivenom.
Bushmaster - up to 12 ft. long, wet tropical forests of C and S America; few bites occur, but mortality rate is high.
Common or Asian cobra - 4 to 8 ft. long, throughout S Asia; considerable tissue damage, sometimes paralysis; mortality probably not more than 10%; antivenom.
Copperhead - less than 4 ft. long, from New England to Texas; pain and swelling; very seldom fatal; antivenom seldom needed.
Coral snake - 2 to 5 ft. long, in Americas south of Canada; bite may be painless; slow onset of paralysis, impaired breathing; mortalities rare, but high without antivenom and mechanical respiration.
Cottonmouth water moccasin - up to 5 ft. long, wetlands of southern U.S. from Virginia to Texas. Rapid onset of severe pain, swelling; mortality low, but tissue destruction can be extensive; antivenom.
Death adder - less than 3 ft. long, Australia; rapid onset of faintness, cardiac and respiratory distress; at least 50% mortality without antivenom.
Desert horned viper - in dry areas of Africa and western Asia; swelling and tissue damage; low mortality; antivenom.
European vipers - from 1 to 3 ft. long; bleeding and tissue damage; mortality low; antivenoms.
Gaboon viper - over 6 ft. long, fat; 2-inch fangs; south of the Sahara; massive tissue damage, internal bleeding; few recorded bites.
King cobra - up to 16 ft. long, throughout S Asia; rapid swelling, dizziness, loss of consciousness, difficulty breathing, erratic heartbeat; mortality varies sharply with amount of venom involved, most bites involve nonfatal amounts; antivenom.
Kraits - up to 5 ft. long, in S Asia; rapid onset of sleepiness; numbness; up to 50% mortality even with antivenom.
Puff adder - up to 5 ft. long, fat; south of the Sahara and throughout the Middle East; rapid large swelling, great pain, dizziness; moderate mortality often from internal bleeding; antivenom.
Rattlesnake - 2 to 6 ft. long, throughout W. Hemisphere. Rapid onset of severe pain, swelling; mortality low, but amputation of affected digits is sometimes necessary; antivenom. Mojave rattler may produce temporary paralysis.
Ringhals, or spitting, cobra - 5 ft. and 7 ft. long; S Africa; squirt venom through holes in front of fangs as a defense; venom is severely irritating and can cause blindness.
Russell's viper or tic-polonga - over 5 ft. long, throughout Asia; internal bleeding; moderate mortality rate; bite reports common; antivenom.
Saw-scaled or carpet viper - up to 2 ft. long, in dry areas from India to Africa; severe bleeding, fever; high mortality, causes more human fatalities than any other snake; antivenom.
Sea snakes - throughout Pacific, Indian oceans except NE Pacific; almost painless bite, variety of muscle pain, paralysis; mortality rate low, many bites are not envenomed; some antivenoms.
Sharp-nosed pit viper or One Hundred Pace Snake - up to 5 ft. long, in S Vietnam and Taiwan, China; the most toxic of Asian pit vipers; very rapid onset of swelling and tissue damage, internal bleeding; moderate mortality; antivenom.
Taipan - up to 11 ft. long, in Australia and New Guinea; rapid paralysis with severe breathing difficulty; mortality nears 100% without antivenom.
Tiger snake - 2 to 6 ft. long, S Australia; pain, numbness, mental disturbances with rapid onset of paralysis; may be the most deadly of all land snakes though antivenom is quite effective.
Yellow or Cape cobra - 7 ft. long, in southern Africa; most toxic venom of any cobra; rapid onset of swelling, breathing and cardiac difficulties; mortality high without treatment; antivenom.
Note: Not all bites by venomous snakes are actually envenomed. All animal bites, however, possibly carry tetanus, and anyone suffering a snake bite should seek medical attention. Antivenoms do not cure; they are only an aid in the treatment of bites. Mortality rates above are for envenomed bites; low mortality, up to 2% result in death; moderate, 2-5%; high, 5-15%.
