Heteroneris is a

Options

A. another name of Nereis
B. genus of an annelid
C. asexual phase of Nereis
D. sexual phase of Nereis

Answer

**Step-by-Step Solution:**

1. **Understanding Heteronereis**: Heteronereis is a term that refers to a specific phase in the life cycle of certain marine organisms, particularly within the Nereis genus.

2. **Identifying the Options**: The question provides four options:
- A) Another name of Nereis
- B) Genus of an annelid
- C) Asexual phase of Nereis
- D) Sexual phase of Nereis

3. **Analyzing the Options**:
- Option A (Another name of Nereis) is incorrect because Heteronereis is not simply another name for Nereis.
- Option B (Genus of an annelid) is misleading as Heteronereis is not a genus but rather a phase related to Nereis, which is a genus of annelids.
- Option C (Asexual phase of Nereis) is incorrect because Heteronereis refers to the sexual phase, not the asexual phase.
- Option D (Sexual phase of Nereis) is correct as Heteronereis represents the reproductive stage of Nereis.

4. **Conclusion**: After evaluating the options, the correct answer is D) Sexual phase of Nereis.

5. **Additional Information**: Heteronereis is characterized by being a free-swimming organism with dimorphic sexual individuals, meaning there are distinct male and female forms. The males and females exhibit differences in their posterior and anterior segments.