Why is there no marine amphibian?

Explanation

### Step-by-Step Solution:

1. **Understanding Amphibians**: Amphibians are a class of animals that typically have a life cycle that includes both aquatic (larval) and terrestrial (adult) stages. They have thin skin that is permeable to water and gases.

2. **Defining Marine Environment**: The marine environment refers to ocean waters, which have a high salt concentration (salinity). This high salinity is significantly different from the freshwater environments where amphibians are commonly found.

3. **Skin Adaptation**: Amphibians have skin that is adapted to live in environments with lower salinity. Their skin is thin and allows for gas exchange and moisture absorption, but it is not suited for high salinity conditions.

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