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The most venomous land snake on earth…

The Inland Taipan

Olivier DUBOIS

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Commonly called :The Inland Taipanthe Small Scaled SnakeFierce Snake

Name.

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Class: ReptiliaSuborder: SerpentesFamily: ElapidaeSpecies: Oxyuranus microlepidotus

Scientific classification.

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Habitation.

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Colour :Depanding on seasons,from a rich, dark hue to a brownish olive-

green.The darker colour allows the snake to heat itself while only

exposing a smaller portion of the body

Appearance.

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Lenght : Average 1.8 m Up to 2.5 m

Eyes : brown iris coloured rim around the pupil

Appearance.

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Lives in burrows.

Eats rodents (mice, rats), birds.

Habitation & diet.

Killing method: One single accurate

bite, waiting for the prey

to die, then returning to

safely consume its meal

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Look at it closer…

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Do you fear it ?

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You should because…

…its venom is 200-400 times more toxic than most rattlesnakes and 50 times as toxic as a cobra

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LD50 (lethal dose 50%) test :Dosing animals with a substance By mouth, by injection or inhalationTest is done when half of the animals in the

group have died

Indicates the standard toxicity value for a chemical

Venom.

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Venom yield for one bite : 44.0-110.0 mgSub-cutaneous LD50 0.025 mg/kg

One bite could cause the death of about 100 human beings.

Venom.

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Risks for one bite.

neurotoxic paralysis

coagulopathy

headache

nausea

abdominal pain

loss of consciousness

convulsions

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Risks for one bite.

neurotoxic paralysis

coagulopathy

acute renal failure

headache

nausea

abdominal pain

loss of consciousness

convulsions

Myotoxicity

Cardiotoxicity

Anticoagulant Effects

Hemolytic Activity

Internal Hemorrhage

Edema Inducing Activity

Organ or Tissue Damage

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Risks for one bite.

neurotoxic paralysis

coagulopathy

acute renal failure

headache

nausea

abdominal pain

loss of consciousness

convulsions

Myotoxicity

Cardiotoxicity

Anticoagulant Effects

Hemolytic Activity

Internal Hemorrhage

Edema Inducing Activity

Organ or Tissue Damage

DEATH

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Taipoxin Paradoxin (neurotoxins)Oxylepitoxin-1 (neurotoxin)…And some phospholipases A2 enzyme

(vPLA2s)

Venom components.

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Participate in :Digestion of prey Venom toxicity (including neurotoxicityn myotoxicity,…)

Are natural endogenous ligands (binds to other chemical entities, act as a catalyser)

Therapeutics prescriptions :Lipid digestionHost defense mechanisms :

inflammation defenseAntibacterial defense

vPLA2s’ proprieties.

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Receptors, binding proteins for vPLA2s have been identified in mammals (not only in venomous animals !)

Do a diversity of mammalian secrete vPLA2s enzyme ? A scientific study shows that sPLA2 fold has been used by both

snakes and mammals to generate various proteins with specific biological effects.

Snakes and other venomous animals elaborate sPLA2s distinct from those produced by venom glands to support physiological functions

vPLA2s’ proprieties.

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Venom glands thought to have evolved from digestive glands

A single snake venom… can contain a variety of vPLA2s (up to 15 distinct

enzymes) The genes for these vPLA2s are likely to have

evolved through positive Darwinian selection.

Evolution.

Is this positive Darwinian selection ?

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Deadly does not mean dangerous !

Is shy and secretive, prefers to escape from trouble,bites only if threatened.

To be fair…