Enterobius vermicularis

Enterobius vermicularis. Adult female pinworm (unstained, low power). Adult pinworms are readily identified morphologically by the characteristic dorsoventral cephalic inflations of the cuticle and the shape and structure of the esophagus, ie, divided into muscular and bulbous portions separated by a short, narrow isthmus as seen in this view of the anterior portion of a female worm. Eggs within the uterus are also visible.