Physaloptera species are found worldwide and infect such varied animals as hedgehogs, doves, and monkeys. The adult Physaloptera looks like a short version of the roundworm, and that is where it causes some confusion. If found in a cat or dog's vomit, it may easily be mistaken for a roundworm. The eggs of Physaloptera and roundworms are both found in the feces, but differ in appearance.
The adult worm attaches itself to the stomach wall of cats and dogs, and its eggs are passed in the feces. The eggs, which contain larvae, are ingested by beetles. A cat or dog eating the insect then becomes infected.
Physaloptera is found in most of the United States, and is generally not felt to be an important cause of disease, however, it may cause bleeding in the stomach. In severe infections, vomiting, loss of appetite, and black, tarry feces may be seen. There is no known treatment, however, the newer wormers, such as fenbendazole, may be effective.