A 3-year-old captive corn snake (Pantherophis guttatus) was taken our veterinary clinic with a complaint of intermittent body swelling. Radiography revealed soft-tissue swelling, and ultrasonography confirmed intussusception of the digestive tract. Celiotomy revealed esophagogastric intussusception, which was subsequently corrected. Histopathological examination of gastric mucosal biopsy and polymerase chain reaction (PCR) from feces were revealed protozoan parasitism within the lesion and detected specific genes …