Dispharynx nasuta (also called Acuaria spiralis, Dispharynx spiralis, and Synhimantus nasuta) is a parasitic roundworm, or "stomach worm" from the Acuaria genus of roundworms. These worms are known to invade many different poultry species. It is found throughout the Americas, Asia and Africa. D. nasuta invades the lining of the chicken's proventriculus (stomach) and esophagus, and sometimes the small intestines.
D. nasuta have an indirect life cycle as adults lay their eggs in the proventriculus of infected birds, which get shed in their feces. Other birds become infected by either consuming contaminated soil, feed or water with the feces and embryonated eggs, or by consuming an intermediate host contaminated with the eggs---sowbugs or water lice.
Numerous classic broad spectrum anthelmintics are effective against Acuaria worms, e.g. several benzimidazoles (albendazole, fenbendazole, flubendazole, mebendazole, oxfendazole, etc.), levamisole, as well as macrocyclic lactones (e.g. ivermectin).