One of the amphibians have gills

Options

A. Amphiuma
B. Ichthyophis
C. Necturus
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which amphibian has gills. We need to identify amphibians that possess gills during their life cycle.

2. **Analyzing the Options**: The options provided include Amphura, Istiophis, and Necturus. We need to evaluate each option to determine if they are amphibians and if they possess gills.

3. **Evaluating Amphura**:
- Amphura is mentioned as not being an amphibian but rather belonging to the phylum Echinodermata, which includes invertebrates.
- Therefore, Amphura cannot be the correct answer.

4. **Evaluating Istiophis**:
- Istiophis is identified as a salamander, which is an amphibian.
- It is noted that Istiophis has gills during its larval stage, but these gills are lost as it matures into an adult, transitioning to skin respiration.
- Thus, while Istiophis has gills, they are not present throughout its entire life cycle.

5. **Evaluating Necturus**:
- Necturus is also a salamander and belongs to the order Eurodella.
- It is highlighted that Necturus retains its gills and gill slits throughout its entire life cycle, from larva to adult.
- This characteristic makes Necturus unique among the options provided.

6. **Conclusion**: Based on the evaluations, Necturus is the amphibian that has gills throughout its life cycle. Therefore, the correct answer is Necturus.

**Final Answer**: Necturus is the amphibian that has gills.

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