Snakes are extremely dangerous species of reptiles and no doubt they appear among the most feared creatures on the planet. One significant feature about these limbless moving reptiles is their ability to eject toxic venoms from a bite. These venoms do posses lethal threats to other organisms, thereby making the snake a very fearsome hunter in the wild. Trust me you really don't want to mess around the snake's territory.
Out of the 3,500 snake species found on Earth, only 600 of them are actually capable of ejecting venoms from a bite. These venoms comes in different levels of lethality depending on the amount of toxin found in it. Studying about venoms is quite complex, and snake venom works differently on different creatures. Due to this, several criteria has thus been adopted when listing the most venomous snakes. Some lists are based on how many mice or humans one bite from a snake would kill. Other lists are more interested in the number of human deaths recorded each year from the snake. However the standard way of measuring the degree of lethality posed by a snake's venom or otherwise known as it "toxicity" is from the median lethal dose(LD50). The median lethal dose or LD50 is the dose of venom needed to kill 50%(half) the members of a group of tested animals after a specified duration. The animal mostly used for this tests are the mice. A lower LD50 is an indication of increased toxicity.
In our list, we're going to highlight 8 of the most venomous snake species found on earth based on the median lethal dose for mice.
INLAND TAIPAN
Inland Taipan
When it comes to the amount of toxin found in a venom, the Inland Taipan is by far the most venomous snake in the world. Being nicknamed as the "fierce snake", a single bite from an Inland Taipan can deliver a maximum of 110mg of it venom, being so toxic enough to kill at least 100 adult humans or 250 thousand mice. Although being so venomous, it has less defensive disposition unlike it counterpart "the coastal Taipan" and it shy by nature. Hence very few humans have been bitten and no human death has ever been recorded from an Inland Taipan.
VENOM REVIEW
Rating : Extremely toxic
dose ejected : 44mg
Maximum dose recorded : 110mg
Median lethal dose for mice : 0.025mg/kg
Components of venom and envenomation
Neurotoxins, hemotoxins, myotoxins, nephrotoxins, haemorrhagin, hyaluronidase enzyme.
Envenomation can lead rise to paralysis (such as respiratory failure and pneumonia), coagulopathy(such as cerebral haemorrhage and kidney failure), and cardiac complications.
EASTERN BROWN SNAKE
Eastern brown snake
A specie of extremely venomous snake found mostly in the eastern and central Australia and New Guinea.
The eastern brown snake is considered the second most venomous snake, only behind the inland taipan based on it LD50 value in mice. A bite from an eastern brown snake can deliver enough venom, toxic enough to kill 212,000 mice or 58 humans. It responsible for about 60% of snake bite death in Australia.
VENOM RATING : Extremely toxic
Average dose of venom ejected : 5mg
Maximum dose recorded : 67mg
Median lethal dose for mice : 0.0365mg/kg
Components of venom and envenomation
Neurotoxins, hemotoxins.
The eastern brown snake envenomations are characterized by DIC(disseminated intravascular coagulopathy) and VICC(venom-induced consumptive coagulopathy). Both cases can lead to haemorrhage, cardiovascular depression, renal failure, paralysis, hypotension, and collapse.
Death is mostly due to cardiovascular causes like cardiac arrest or intracranial hemorrhage (bleeding within the skull).
SEA SNAKES
Sea Snakes are more numerous than terrestrial venomous snakes. So for equality sake, we'll group them into one classification.
Sea Snakes(or coral reef snakes) are extremely venomous snakes belonging to the family elapidae and are common in tropical and subtropical regions bordering the Indian and Pacific oceans. The venoms of sea snakes contains potent neurotoxins which are some of the most toxic substances in the world. They are more toxic than venoms of terrestrial snakes, including rattlesnakes, copperheads, and cobras. Molecular weights of sea snakes neurotoxins are about 6800g/mol.
The Dubios's sea snake is the most venomous of them all, having a median lethal dose of 0.044mg/kg when injected subcutaneously to mice.
Dubios's sea snake
After the Dubios's sea snake comes the yellow bellied sea snake with a subcutaneous lethal dose of 0.067mg/kg.
Yellow bellied sea snake
The last on the sea snake category is the Horned sea snake having a subcutaneous lethal dose of 0.079mg/kg.
Horned sea snake
COASTAL TAIPAN
Coastal Taipan
The coastal taipan is the 3rd most venomous terrestrial snake in the world with a subcutaneous lethal dose of 0.99mg/kg and a recorded venom yield of 400mg. Just behind the inland taipan and the eastern brown snake with lethal doses of 0.0225mg/kg and 0.0365mg/kg respectively. The eastern brown snake may produce venom twice as toxic as that of the coastal taipan, but the coastal taipan produces up to 20 times more venon than the eastern brown snake, and it far more aggressive than the inland taipan, therefore making the coastal taipan one of the most deadliest snakes on the planet in all perspective.
Like other extremely venomous snakes, the coastal taipan is also native to the coastal regions of northern and eastern Australia and also the island of New Guinea.
MANY BANDED KRAITS
This particular snake specie is generally found in the Asian regions including the central and southern China, Taiwan, Hong Kong, and southeast Asia. They're highly noted for having black and white or black and yellow bands all through their length. Their venoms are highly toxic, containing both the pre and post-synaptic neurotoxins which usually bind to block neuromuscular transmission and inhibit the neurotransmitter release due to their specific enzymatic activities.
VENOM REVIEW
Rating: Highly toxic
Average yield: 4.6mg
Maximum recorded venom: 19.4mg
Median lethal dose for mice: 0.108mg/kg
Composition: presynaptic neurotoxins, post-synaptic neurotoxins.
CONGO WATER COBRA
The Congo water cobra is a semi-aquatic snake which spends much of it time in the water. It has a small geographical range, only occuring in just small portions of Western and southern democratic Republic of Congo and some parts of Gabon and Angola. The Congo water cobra like other cobras is equally highly venomous with venom having deadly neurotoxic content. But with a subaneous lethal dose of 0.12mg/kg, the N. Christy venom is more toxic than other cobra species, even more than the Caspian cobra which was believed to hold that position. But since the N. Christy's venom is not extensively studied, many sources still regard the Caspian cobra as the most venomous cobra species.
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