Heterakis

Heterakis is a genus of parasitic nematodes. Members of the genus are minute roundworms (pinworms), hardly 1 cm long, infecting different species of gallinaceous birds, including chickens, turkeys, ducks, geese, grouse, guineafowl, partridges, pheasants, and quail. About 10 species are placed in the genus, but classification is often ambiguous due to their close resemblance, and a number of synonyms have arisen. H. gallinarum Schrank, 1788; H. isolonche von Linstow, 1906; and H. dispar Schrank, 1870 are the best understood species in terms of prevalence, pathogenicity, and biology. They inhabit the lumen of the cecum of the host.