Name the peculiar cell type found in Porifera and Coelonterata.

Explanation

### Step-by-Step Solution:

1. **Identify the Organisms**: The question asks about a specific cell type found in two groups of organisms: Porifera (sponges) and Coelenterata (cnidarians).

2. **Recall the Cell Type**: The peculiar cell type that is characteristic of both Porifera and Coelenterata is known as "choanocytes."

3. **Describe Choanocytes**: Choanocytes, also referred to as collar cells, line the interior of sponges. They have a unique structure that includes a central flagellum surrounded by a collar of microvilli.

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