Scanning electrom microscopy of mature Fasciola gigantica warms revealed no spines on the tegument of the oral and ventral suckers, the shoulders and the lateral sides of the body.
The spines located on the dorsal surface were tongue shaped, while those on the ventral side were scale-like in appearance. Each spine was divided at its tip into small pointed secondary spines forming a fringe like structure. The number of these secondary spines was about 10-15 per each primary one at the level of the anterior part of the body and increased to about 30-75 at the middle part of the ventral surface.
The differences in the morphological picture of the tegument of the dorsal and ventral surfaces of Fasciola gigantics might be used for disting uishing it from Fasciola hepatica.