Thorax is somewhat coarctate on each side behind. Pupae can be classified into three types&colon; obtect, exarate, and coarctate. There are three types of pupae&colon; obtect, exarate or coarctate. Coarctate pupae develop inside the larval skin. The pupae of Diptera can be obtect, exarate or coarctate. In other groups, described as "coarctate", the appendages are not visible.