Apororhynchus amphistomi is one of seven species in the genus Apororhynchus, a genus consisting of microscopic parasitic worms that attach themselves to the intestinal wall of terrestrial vertebrates. It's distribution is in North America.The parasite was discovered in the summer of 1947 infecting a Canada warbler (Wilsonia canadensis) in Mountain Lake, Virginia and a Parula warbler (Compsothlyphis americana) in Augusta, Georgia, thus making it the third species in its genus to be discovered, and the first species in its genus to be discovered in North America.