• Redia larva is a third intra- molluscan parasitic larva, found in the digestive glands.

• The unique feature of the larva is that it develops from the germ balls present in the sporocyst. Germ balls multiply and give rise to Redia.

• Body is elongated, cylindrical and complex in structure. It measures 1.3 to 1.6 mm in length.

• Anteriorly there is a muscular ring like swelling called as collar. Just beneath the collar is the birth pore. Posteriorly larva contains two process near foot called as lappets, which anchor in the tissue of the snail.

• Body wall is composed of tegument, epithelial layer and delicate mesenchyme. Alimentation consists of mouth, pharynx and elongated gut. Pharynx contains pharyngeal glands.

• Flame cells increase in number and number of twigs are formed. There are still 2 excretory pores.

• Germ balls are present occupying major portion of the body, they differentiate into next larval stage, called cercaria larva. In Fasciola hepatica redia larva with rich nourishment gives rise to secondary generation of redia by germ balls. Daughter redia and cercaria come out from mother redia through birth pore.