Approximately 32% of larvae form a puparium with a long delay after reaching the mature size, while the rest die as larvae. The puparia are bloated with hemolymph. Tanning and sclerotisation of the puparial cuticle is uneven and imperfect, and the cuticle does not prevent evaporation of internal water. Prepupal and pupal moults only occur in the abdomen, Head and thoracic discs do not evaginate. Death of the pupariated adults occurs during the prepupal or early pupal period. A wild-type ring gland implanted into mutant larvae significantly accelerates puparium formation.