Syngamus trachea, referred to often as the Gapeworm, or the redworm, is a species of roundworm which infects the trachea, bronchi, and bronchioles.
Appearance: S. trachea are red colored worms, which are often called “forked worms” because the male and female are always locked in copulation to form a “Y” shape.
Life Cycle: The life cycle of S. trachea can be direct, by ingestion of embryonated eggs or infective larvae, or indirect, by ingestion of earthworms or other invertebrates (slugs and snails) containing free or encysted gapeworm larvae. Infected birds will usually pass the female gapeworm eggs in their droppings. Once in the environment, the eggs will embryonate and hatch in about 8–14 days. Earthworms, slugs, and snails become infected by ingesting the gapeworm larvae, where the larvae enter the body cavity and invade the body musculature and encyst. There, they remain infective to birds for several years.