How does a planula larva become a cnidarian polyp?

The planula larva is a ciliated, motile stage in the life cycle of many cnidarians. After a period of swimming or crawling, the larva undergoes a transformation to become a polyp through the following process:

• Attachment: The planula settles and attaches itself by its forward end to a solid object or firm substratum.1
• Metamorphosis: Once anchored, the larva develops tentacles around its posterior end.1
• Maturation: Through this development, the cylindrical body form of the polyp is established, with the mouth and surrounding tentacles facing upward, opposite the point of attachment.12

In most cnidarian life cycles, this polyp serves as a juvenile form that may later produce medusae asexually, though in anthozoans, the polyp is the primary body form throughout the life cycle.2