Herdmania does not has most of chordate characters in adult stage. Then why it is placed in phylum chordates.

Explanation

### Step-by-Step Solution

1. **Understanding Herdmania**: Herdmania is an organism that belongs to the subphylum Urochordata, which is part of the phylum Chordata. It is important to note that while it is classified under chordates, it exhibits significant differences in its adult form compared to typical chordate characteristics.

2. **Chordate Characteristics**: Chordates are generally characterized by the presence of a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some stage of their life cycle. In Herdmania, these features are present in the larval stage but are absent in the adult stage.

3. **Larval vs. Adult Stage**: In the larval stage, Herdmania possesses the typical chordate features: a notochord, a tail, and a hollow nerve cord. However, as it matures into the adult form, these features undergo significant changes and are lost.

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