Piles

Piles ( lat. Strongylidae ) - a family of class of roundworms, or nematodes (Nematodes), leading a parasitic lifestyle. Adults have a length of 1.5 to 5 cm. They are characterized by an enlarged anterior intestine (albeit inconsistent), forming a mouth cavity and a capsule, sometimes equipped with special hooks, 6 papillae surrounding the mouth , and a bell-shaped extension of the posterior end of the body in males, forming the so-called copulation bag ( bursa copulatrix ), armed with two (rarely one) spicules . The family of piles includes 7 genera , with many species parasitizing in the adult state not only in the intestine , but also in other organs of vertebrates, mainly mammals. Some species are very dangerous worms for human life.

Typical body structure of piles:
1 - front end of the body, carrying a mouth; 2 - intestines ; 3 - cesspool ; 4 - excretory system ; 5 - testis ; 6 - nerve ring; 7 - a dorsal nerve ; 8 - ventral nerve trunk ; 9 - excretory hole.