The parasite occurs in the midgut and often in the lumen of the anterior midgut caecum, the primary ducts of the hepatopancrease, the posterior stomach and in the anterior portion of the hindgut. Significant lesions typically occur in heavy infections and consist of a reduction in the height of the midgut mucosa, hyperplasia of the midgut epithelium to form villus-like folds, and perforations of the midgut mucosa.