Difference Between Venomous and Nonvenomous Snakes

Venomous vs Nonvenomous Snakes

Identifying the difference between venomous and nonvenomous snakes would not be very difficult if you know the common features of venomous snakes. In fact, most venomous snakes share some common features among them. Snakes are vertebrates and belong to Class Reptilia. Reptiles are highly adapted to live in various habitats and exhibit three fundamental characteristic features, namely; (a) lay amniotic eggs, (b) presence of dry skin and (c) thoracic breathing. Snakes are categorized under Order Squamata. There are about 3000 species of snakes identified so far. The characteristic feature of the snakes is the presence of paired copulatory organs in males. Snakes are carnivores and feed mainly on insects and small animals. Depending on the presence of  venom, snakes are divided into two groups; venomous and nonvenomous snakes. These two groups of snakes can be identified by several morphological features.

What are Venomous Snakes?

Venomous snakes are the snakes capable of producing  venoms. Snakes like cobras, vipers, and closely related species of snakes are considered as venomous snakes. Some snake venoms are extremely venomous whereas some are mildly venomous. Venomous glands are the modified salivary glands. Venomous snakes deliver venom through fangs. Hence, the presence of fangs is a characteristic feature of most venomous snakes. Most advanced snakes including vipers and elapids have a hollow tube inside their fangs to deliver venoms more effectively. However, rear-fanged snakes like Boomslang, tree snakes have a groove on the posterior edge of the fang to deliver venom. The amount and type of venoms are usually prey specific and used mainly to exhaust prey. Self-defense is a secondary function of venoms. Venoms are proteins and can be neurotoxic, hemotoxic, or cytotoxic. Most venomous snakes have a triangle-shaped head and elliptical pupils.

Difference Between Venomous and Nonvenomous Snakes

Viper head with fangs

What are Nonvenomous Snakes?

The snakes incapable of producing venoms are known as nonvenomous snakes. Most of the snakes belong to this category. Some examples for nonvenomous snakes including pythons, boas, bullsnakes, etc. However, bites of nonvenomous large snakes can be extremely painful which may be even fatal because of their tough jaws. Nonvenomous snakes can be easily identified by the absence of fangs, rounded head, and the presence of anal scales in a double row. Since, these snakes have no venoms to exhaust their prey, they use different other methods like squeezing or chewing the prey or swallowing their prey. As a defense mechanism, certain nonvenomous snakes mimic the venomous snakes.

 Venomous vs Nonvenomous Snakes


What is the difference between Venomous and Nonvenomous Snakes?

• Venomous snakes produce venoms, but nonvenomous snakes do not.

• Venomous snakes have fangs to deliver venoms to their prey, whereas no fangs present in nonvenomous snakes.

• Most venomous snakes have a triangle-shaped head, whereas nonvenomous snakes have a rounded head.

• Venomous snakes have elliptical pupils while nonvenomous snakes have round pupils.

• Venomous snakebite results in one or two punctures on the skin of the victim, whereas nonvenomous snake bite results in many punctures on the skin due to maxillary teeth of the upper jaw.

• Venomous snakes normally have distinguishable heat-sensitive pits on the head unlike in nonvenomous snakes.

• Venomous snakes like rattlesnakes have a rattle on its tails, but no such rattles in nonvenomous snakes.

• There is one row of anal scales present in venomous snakes, whereas two rows of anal scales are present in nonvenomous snakes.


Images Courtesy:

  1. Viper head with fangs via Wikicommons (Public Domain)
  2. Python by Mannes Fotos (GFDL 1.3)