Identify the pair having amphicoelous vertabrae

Options

A. Ornithorhyncus and Macropus
B. Ophiophagus and Tropidonotus
C. Scoliodon and Ichthyophis
D. Crocodylus and Hemidactylus.

Answer

**Step-by-Step Solution:**

1. **Understand the Term "Amphicoelous Vertebrae":**
Amphicoelous vertebrae are characterized by having a spindle-shaped center with concave depressions at both ends. This structure allows for flexibility and movement.

2. **Identify the Characteristics:**
- Spindle-shaped center.
- Notochord runs through the center.
- Concave depressions at both ends.

3. **Know the Organisms that Possess Amphicoelous Vertebrae:**
Amphicoelous vertebrae are typically found in fishes and most amphibians.

4. **Analyze the Given Options:**
- **Option 1:** Ornithurinus and Macropus - Macropus belongs to mammals, so this option is incorrect.
- **Option 2:** Ophiophagus and Torrentopus - This option does not represent the correct pair.
- **Option 3:** Poliodon and Ichthyophis - Both belong to groups that have amphicoelous vertebrae (Poliodon is a fish and Ichthyophis is an amphibian).
- **Option 4:** Crocodile and Hemidactylus - This option is also incorrect as they do not have amphicoelous vertebrae.

5. **Select the Correct Answer:**
The correct answer is **Option 3: Poliodon and Ichthyophis**, as both organisms possess amphicoelous vertebrae.