Latin: septum = dividing wall; intestinalis = belonging to the intestine.
The specimens of this species penetrate human cells of the nose, lung, intestine, and those of the urogenital system. Although this species had already been described in the year 1993, its life cycle is still unknown. Spores of this species were found in 2.2 % of all investigated diarrheic stools of AIDS patients. Treatment with albendazole (2 × 400 mg per day) for 4 days led to the disappearance of the symptoms of the disease and to a stop of the excretion of spores within the feces. See Microsporidia.