A venomous anemone
The venomous sea anemones known as nematostella are both predators and prey at different times in their lives.
Nematostella are sea anemones that belong to the Cnidaria family of jellyfish and corals. They begin their life as tiny larvae and grow into animals measuring several inches long. While in the larvae stage, the nematostella fall prey to larger fish but once mature, they become predators themselves, catching shrimp and small fish with their venomous tentacles.
Recent research has shown that the venom of the nematostella changes over the course of its life, adapting to new environments and new demands.