Spiny skinned organisms come under the phylum ________.

Phylum

1. In animals, closely related classes are classified into a phylum.
2. Echinodermata is a type of phylum belonging to Kingdom Animalia.
3. Echinodermata are spiny-skinned organisms and are exclusively marine animals and live only in the sea.
4. The spiky body of an Echinodermata shows radial symmetry.
5. An example of Echinodermata includes starfish.

Final answer:
Spiny-skinned organisms come under the phylum Echinodermata.