Marine posinous snake is characterised by

Options

A. Body colour
B. Pit between nostrils
C. Round tail
D. Laterally compressed tail

Answer

**Step-by-Step Solution:**

1. **Understanding Marine Poisonous Snakes**: Marine poisonous snakes are a unique group of reptiles that are adapted to living in marine environments. They are known for their ability to thrive in saltwater and have specific adaptations that distinguish them from terrestrial snakes.

2. **Identifying Characteristics**: The question asks for the characteristic feature of marine poisonous snakes. The options provided are:
- Body colour
- Pit between nostrils
- Round tail
- Laterally compressed tail

3. **Analyzing Each Option**:
- **Body Colour**: While body colour can vary among marine snakes, it is not a defining characteristic that distinguishes them as a group.
- **Pit Between Nostrils**: This feature is more commonly associated with certain terrestrial snakes, such as pit vipers, and is not a characteristic of marine snakes.
- **Round Tail**: Marine snakes do not typically have round tails; this feature is more common in some terrestrial snakes.
- **Laterally Compressed Tail**: Marine poisonous snakes are characterized by having laterally compressed tails, which aid in swimming. This adaptation allows them to move efficiently in water.

4. **Conclusion**: The correct answer is that marine poisonous snakes are characterized by a laterally compressed tail. This feature is crucial for their aquatic lifestyle and distinguishes them from other snake species.

**Final Answer**: Marine poisonous snakes are characterized by a laterally compressed tail.

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