part of develops into wing disc primordium wing blade wing pouch Region of dorsal mesothoracic disc that will develop into the wing blade. Its boundary is delimited by folds in the third instar disc epithelium. The cells in this region can also be distinguished from surrounding cells in the third instar disc by their basal accumulation of lipid granules. The wing pouch is bisected by the anterior-posterior compartment boundary of the disc. fly_anatomy.ontology FBbt:00006029 wing primordium cuboidal/columnar epithelium