The phylum characterized by the presence of a false coelom is ________.

Explanation

**Step-by-Step Solution:**

1. **Understanding Coelom Types**:
- Coelom is a body cavity that is present in many animals. It can be classified into three types: true coelom, pseudocoelom, and acoelom.
- A true coelom is a body cavity that is completely lined by mesoderm. A pseudocoelom, on the other hand, is a body cavity that is not completely lined by mesoderm.

2. **Identifying Pseudocoelomate Animals**:
- Animals that possess a pseudocoelom are referred to as pseudocoelomates. In these organisms, the body cavity is present between the mesoderm and endoderm but is not entirely lined by mesoderm.
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