Phylum - Chordata
Sub phylum - Reptilia
Order - Ophidea
Snakes are of two types :
Non- poisonous Snakes
Majority of the snakes are non venomous. It is important to know about the poisonous snakes and the which part of our body is affected by the venom.
Poisonous snakes :When a poisonous snake bite, it releases poison which can even cause death. Some important characteristics of poisonous snakes are:
1)Snakes are smaller in size.
2)Over lap shields are larger in size and they are joined at edges.
3)Scales on dorsal side are called dorsals or costals.
4)Scales on ventral side are called ventrals.
5)Scales in tail region are called codals.
6)If the ventrals are large and stretch the entire belly these are poisonous snakes.
7)If the tail is cylindrical and dorsal flattened it is poisonous.
8)If the tail is round or blant it is non- poisonous.
9)If the fang impression is found it is poisonous.
Poisonous gland of snake : The salivary gland is modified to secrete the poisonous fluid.
Poisonous fluid is of 2 types:
Neurotoxic fluid and Haemotoxic fluid
Neurotoxic fluid : Affects the nervous system
Example :- Cobra and Krait
Haemotoxic fluid : Affects circulatory system
Example :- Vipers and Sea snakes
The most poisonous snakes found in India are:
Cobra : Cobra are of two types
1. Naja Naja (Indian Cobra )
2. Naja Hannaha (King cobra )
Characteristics of Cobra snakes:
1)Cobras have a hood. The neck gets extended and is called hood.
2)It is supported by ribs.
3)The hood posses a spectacle mark.
4)The head is covered by shields.
5)The 3rd supra rabeil (found) touches the nasal and the eye.
6)The ventrals are large and stretch the belly.
7)They are found where there is a thick vegetation.
8)These have neurotoxic fluid.
9)They produce a hissing noise.
10)They measure 8-10 feet
Characteristics of Krait snakes:
1)They measure 6-8 feet in size.
2)They are poisonous.
3)They have neurotoxic fluid.
4)Alternating dark and white bands are found.
5)The 4th infra rabiel is the largest.
6)The tail is cylindrical and pointed.
Vipers are deadly poisonous.
They are of 3 types:-
1. Pit Viper
2. Pitless Viper
3. Russels Viper
Characteristics of Vipers:
1)This have haemotoxic fluid.
2)Head is covered by scales.
Sea snake :
Characteristics of Sea snakes:-
1)It is found in sea.
2)It measures 4-5 feet in size.
3)Tail is laterally compressed to form a oar shaped structure.
4)They have neurotoxic fluid.
Non- poisonous snakes
Commonly found non poisonous snakes in India are :
Rat snake and python
1)Python is a large massive snake.
2)It measures about 25 feet.
3)It is found on trees.
4)It has a coiled tail.
5)It is very important because it has remmants of pelvic girdle, these shows that snakes had limbs.
Rat Snake :
1)It is found in paddy fields.
2)It feeds on rats.
3)It measures 3-4 feet in size.
Sand Boa :
1)It measures 6-8 feet in size.
2)The colour matches the sand.
3)Head and tail are alike.
4)It is found in the sand.
5)It uses its tail as defensive measure.
6)It is also called double headed snake
Water Snake :
1)It measures 2-3 feet in size.
2)It is found in water.
3)It feeds on aquatic organisms.
The classification of snake poison can be made in to 3 division, not as 2 as author had mentioned,
1.Heamotoxic ( acts on Blood)
2.Mayo-toxin (acts on skeletal Muscles
3.Neuro toxin (acts nervous system).
as snakes swallows whole animal without biting /chewing etc,it becomes essential to digest them with very high concentration of enzymes.these venom not only paralyzes the prey but internally digest prey, so that it becomes very easy to digest inside snakes body.
technicalities of article may have to verified with herpetologist.