A connecting link between two phyla is

Options

A. Archaeopterys- Aves and Mammalia
B. Amphioxus- Echinodermata and Chordata
C. Peripatus- Annelida and Arthropoda
D. Ornithorhyncus - Aves and Reptilia.

Answer

To solve the question "A connecting link between two phyla is," we will analyze the options provided and determine which one serves as a connecting link between two distinct phyla.

### Step-by-Step Solution:

1. **Understanding the Question**:
- We need to identify an organism that serves as a connecting link between two different phyla.

2. **Analyzing the Options**:
- **Option 1: Archaeopteryx (between Aves and Reptilia)**:
- Archaeopteryx is often considered a transitional fossil between reptiles and birds (Aves). However, it does not connect mammals and apes, so this option is incorrect.

- **Option 2: Amphioxus (between Chordata and other phyla)**:
- Amphioxus is a primitive chordate that exhibits features of both invertebrates and vertebrates. However, it does not serve as a connecting link between two specific phyla, so this option is incorrect.

- **Option 3: Hipparthus (between Annelida and Arthropoda)**:
- Hipparthus is a genus that shows characteristics of both annelids (segmented worms) and arthropods (insects, crustaceans, etc.). The presence of features such as nephridia (in annelids) and jointed legs (in arthropods) indicates a connection between these two phyla. Therefore, this option is correct.

- **Option 4: Ornithorhynchus (between Mammalia and Reptilia)**:
- Ornithorhynchus, or the platypus, is a monotreme that does not serve as a connecting link between mammals and reptiles. It is a unique mammal but does not connect the two phyla, making this option incorrect.

3. **Conclusion**:
- The correct answer is **Hipparthus**, which serves as a connecting link between the phyla **Annelida and Arthropoda**.

### Final Answer:
The connecting link between two phyla is **Hipparthus (Annelida and Arthropoda)**.

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