develops from imaginal disc primordium larval imaginal tissue imaginal disc fly_anatomy.ontology A sac shaped epithelial structure in the larva that gives rise to part of the adult integumentary system. One side of the sac consists of peripodial epithelium, the other of columnar epithelium. A single anterior-posterior compartment boundary bisects both peripodial membrane and columnar epithelium. Cells do not cross this boundary during growth and development of the disc. UBERON:0000939 FBbt:00001761 imaginal disk multi-tissue structure ventral ectoderm derivative