Question

When tail is cylindrical and vertical scales do not extend the entire width of the belly, snake is
A. Non-poisonous
B. Definitely poisonous
C. Deadly poisonous
D. Either poisonous or non-poisonous

Answer 1

Hint: Both poisonous and venomous animals are toxic. The venomous animals are those which can deliver or inject the toxin/venom directly into the body of another animal, while poisonous animals are those which are toxic only if they are eaten or touched. It means the poisonous animal does not produce venom. In another word we can understand as if an animal bites you and you die then the animal is venomous and if you bite the animal and you die then it is poisonous.

Complete answer:
The snake is venomous or not it can be identified by careful observations of the following structures:
1. Nature of the tail:
First observe the tail.
• Tail is flat and compressed laterally - Sea snake - Venomous.
• If the tail is short and blunt - Sand Boa -Non venomous
• And if the tail is round and cylindrical - Venomous/Non venomous

2. Nature of the ventral scales:
If the snake has a cylindrical tail it can be venomous or non-venomous.
• Small scales on the ventral side (belly region) – Non-venomous (Garter snake),
• The belly region is not covered completely with larger ventral scales and small scales at the end of broad ventral scales – Non venomous (Python).
• And if the Ventral scales cover the entire width of the belly region and are broad - Venomous/ Non venomous.

3. Nature of the head scales:
• Small head scales – Venomous
• Has large shield in the head – can be Venomous or Non venomous

4. Nature of the vertebral scales and jaw scales:
If the vertebral scales are not large, the third supra labial shield (upper jaw) is large and touches the nostril and eye - Venomous-( Cobra or coral snake).
And if the Vertebral scales are large and hexagonal, four infra labial scales with 4th one is the largest - Venomous – (Krait).

Hence the correct answer is Option(A)

Note: In India, approximately 60 venomous species are found, out of which four are the deadliest i.e. Russell’s viper, Common krait, Indian cobra, Saw-scaled viper.