A genus of nematodes that infect birds; members of the family Acuariidae.
- S. spiralis, S. nasula — found in the walls of the proventriculus, esophagus, and sometimes intestine of most domestic and wild bird species, mainly in water birds, e.g. pelicans, but also in hawks and owls. It causes severe lesions in the proventriculus and affected birds waste away and die. Losses may be heavy.
