Which is the Most Venomous Snake?

Which is the most venomous snake?

A frequently asked question about venomous snakes and snakebites involves which snakes are the most venomous. "Most venomous", however, may mean different things to different people. It may relate to toxicity studies. Since these are usually preformed in mice or other laboratory animals, they may be of limited relevance to humans.

A commonly cited list, from Struan Sutherland's text "Australian Animal Toxins" (1983), is included below, with additional information from the "Handbook of Clinical Toxicology of Animal Venoms and Poisons" by Meier and White (eds) 1995.

Snake

Species

LD50 (mg/kg) in saline by subcutaneous injection in mice

Average venom yield (mg)

Max venom yield (mg)

Fierce snake
(=inland taipan, small scaled snake)

Oxyuranus microlepidotus

0.025

44

110

Eastern brown snake

Pseudonaja textilis

0.053

2-6

67

Coastal taipan

Oxyuranus scutellatus

0.099

120

400

Tiger snake

Notechis scutatus

0.118

35

189

Black tiger snake

Notechis ater niger

0.131

  

Beaked sea snake

Enhydrina schistosa

0.164

  

Black Tiger snake

Notechis ater occidentalis

0.194

  

Black Tiger snake

Notechis ater serventyi

0.338

  

Death Adder

Acanthophis antarcticus

0.400

78

236

Gwardar
(= western brown snake)

Pseudonaja nuchalis

0.473

18

 

Spotted brown snake

Pseudonaja guttata

0.36 (in bovine serum albumin)

  

Australian copperhead

Austrelaps superbus

0.56

20

85

Cobra

Naja naja

0.565

169

610

Dugite

Pseudonaja affinis

0.66

18

 

Papuan black snake

Pseudechis papuanis

1.09

  

Stephens' banded snake

Hoplocephalus stephensii

1.36

  

Rough scaled snake
(= Clarence river snake)

Tropidechis carinatus

1.36

6

22

King cobra

Ophiophagus hannah

1.80

421

 

Spotted black snake, blue bellied black snake

Pseudechis guttatus

2.13

32

 

Collett's snake

Pseudechis colletti

2.38

48

 

Mulga snake
(= King brown snake)

Pseudechis australis

2.38

180

600

Red bellied black snake

Pseudechis porphyriacus

2.52

40

75

Small eyed snake

Cryptophis nigrescens

2.67

  

Eastern diamond backed rattlesnake

Crotalus adamanteus

11.4

410

848

 

Demansia atra

>14.2

  
 

Bothrops atrox

>27.8

  

Although Australian snakes make up most of this list, the number of snake bites in Australia is relatively, small, and the number of deaths much smaller. 
"Most venomous" may also mean which snakes are associated with the most deaths. This will of course vary from region to region. In Australia, around half of all snakebite deaths involve brown snakes, with all other snakes making up the remaining 50%. On a world scale, however, brown snakes deaths are negligible compared to deaths from cobras, kraits or vipers.