Which of the following is not an invasive alien plant species in India ?

Options

A. Parthenium
B. Eicchornia
C. Lantana
D. Clarias

Answer

To determine which of the following is not an invasive alien plant species in India, we will analyze each option provided:

1. **Parthenium**: This is commonly known as carrot grass and is indeed an invasive alien species in India. It was introduced accidentally and has spread rapidly, causing harm to native flora and fauna.

2. **Eichhornia**: Also known as water hyacinth, this plant is another invasive alien species in India. It has a tendency to grow excessively in water bodies, leading to ecological imbalances.

3. **Lantana**: This is a flowering plant that is also classified as an invasive alien species in India. It has spread widely and poses a threat to native plant species and ecosystems.

4. **Clarias**: This refers to the African catfish, which is a fish species and not a plant. It has been introduced in India and has become invasive, threatening native fish populations.

Based on this analysis, the correct answer to the question "Which of the following is not an invasive alien plant species in India?" is **Clarias**.

### Step-by-Step Solution:
1. **Identify the options**: The options given are Parthenium, Eichhornia, Lantana, and Clarias.
2. **Research each option**:
- Parthenium: Invasive alien plant species in India.
- Eichhornia: Invasive alien plant species in India.
- Lantana: Invasive alien plant species in India.
- Clarias: Not a plant, but an invasive fish species in India.
3. **Determine the non-invasive species**: Since Clarias is a fish and not a plant, it does not fit the category of invasive alien plant species.
4. **Conclude the answer**: The correct answer is Clarias.