Anemones, sea flowers?

Although they look like underwater flowers, anemones are actually animals belonging to the phylum Cnidaria, which also includes jellyfish, corals, and gorgonia.
They are very common in the tidal zone, where they attach to rocks by their base, which they also use to move around. Their body is shaped like a sac, which opens to the outside through a single orifice that functions as both mouth and anus and is surrounded by numerous tentacles.

SEA NETTLES
Anemone tentacles have stinging cells with a coiled filament inside, which they shoot out like a harpoon whenever something touches them, injecting a poison into the body of the victim that is left paralysed.

This poison can also irritate people's skin, eyes, and mouth. For this reason, you should take care when touching anemones.

A FATAL TRAP
The anemone's tentacles are fatal traps for small fish or shrimp that approach them. As soon as they touch them they are paralysed by the stinging cells and are then taken to the mouth to be swallowed.