Prostomium

The prostomium (From Ancient Greek, meaning "before the mouth"; pl.

The prostomium together with the peristomium, which includes the mouth and pharynx, make up the annelid head.

In addition to the eyes, antennae and palps, the prostomium can possess appendages such as tentacles or cirri.

Moreover, some polychaete prostomia have a posterior extension or ridge with sensory function, called a caruncle.

The palps are paired and innervated structures that tend to be located ventrally and laterally.