Read the following informations and identify the genus
* Coralloids roots are with BGA
* Unbranched stem
* Lack ovary wall
* Pinnate leaves

Answer

To identify the genus based on the given information, we can follow these steps:

### Step 1: Analyze the Characteristics
We have the following characteristics to consider:
- Coralloids roots with blue-green algae (BGA)
- Unbranched stem
- Lack of ovary wall
- Pinnate leaves

### Step 2: Understand Each Characteristic
1. **Coralloids Roots with BGA**: This indicates a symbiotic relationship, often seen in certain plants that have a mutualistic association with blue-green algae.
2. **Unbranched Stem**: This suggests that the plant does not have multiple branches coming off the main stem, which is a feature of some specific plant groups.
3. **Lack of Ovary Wall**: This characteristic is indicative of gymnosperms, where the seeds are not enclosed by an ovary wall (naked seeds).
4. **Pinnate Leaves**: Pinnate leaves are typically needle-like and are characteristic of certain gymnosperms, often adapted to reduce transpiration.

### Step 3: Identify the Group
Based on the characteristics, particularly the lack of an ovary wall and the presence of pinnate leaves, we can conclude that this plant belongs to the gymnosperms.

### Step 4: Narrow Down to the Genus
Among gymnosperms, the presence of coralloids roots with BGA is a specific feature of the genus **Cycas**. Cycas is known for having unbranched stems and pinnate leaves, and it forms a symbiotic relationship with blue-green algae in its coralloid roots.

### Conclusion
The genus identified based on the provided characteristics is **Cycas**.

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