These are organisms measuring about 5 to 10 centimeters in length with a cylindrical and segmented body. Most live on the sea floor, but they can be seen under rocks, near areas where algae grow and in corals.

Many species exist, most of these inoffensive to man; but there is a well-known species called the "Worm of Fire" (Hermodice carunculata) that can cause wounds.

Their body has numerous lateral appendixes covered with thousands of fine hairs which, when touched, enter into the skin causing several clinical symptoms.

These include: a local inflammatory reaction, itching, burning sensation and dizziness.

The first thing to do is to remove the hairs from the skin, using adhesive tape for instance; afterwards a treatment for the pain can be
applied, and antibiotics in the event of a secondary infection.

Therefore this worm should not be touched without adequate hand protection.