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Sea anemone are the beautiful, graceful creatures that bloom like flowers on the ocean floor. But beware — within the delicate tendrils of the sea anemone is venom used to paralyze the innocent passersby who may not realize that they are to become the anemone’s lunch!

The tentacles have nematocysts, or stinging cells, that paralyze and entrap their prey. Then, the anemone pulls the stunned creature into its mouth, which is located in the center of the tentacles.

Inside the slit-like mouth exists a short esophagus that opens into the body cavity. At either end of the mouth, there exists a pore which opens into a ciliated groove called a “siphonoglyph.” The siphonoglyph does exactly what its name suggest — it siphons currents of water through the body. This process allows the anemone to take oxygen from the water, and then release waste products which are carried out of the body.

Sea anemone generally reproduce sexually — the eggs are fertilized in the gastric cavity, and the larvae are released out of the mouth. The baby anemone then attach themselves to a surface, where they may remain for a long time. Sometimes, sea anemone attach to the shells of hermit crabs, who carry them around on their shells until the anemone get too big, and have to find a new home.

Attaching themselves to rocks or coral, sea anemone only travel very slowly, if at all, by fluctuating the organ that secures them, called a pedal disk. Some anemones can burrow into the sand, and a few can even swim short distances by bending their column shaped body back and forth, and flapping their tentacles.

Some sea anemone form good friendships with clownfish or anemonefish. These colorful fish like to hang around the anemone and snack on edible debris entangled in their tentacles. Unlike other fish, clownfish have developed a mucus coating around their bodies, which protects them from the stinging cells of the anemone. They make a colorful and fascinating couple.

You can visit sea anemone at the aquarium, or else look for them in tide pools and tropical coral reefs. But, remember, look but don’t touch. You could get stung by the pretty sea creature. You might be clowning around, but you’re no clownfish!