tracheal system________________________
segmental subdivision of organ system__|
                                       tracheal metamere
                                        |__thoracic tracheal metamere  126 rec.
                                            |__tracheal metamere 1 121 rec.
                                            |   |__adult spiracular tracheal branch 1
                                            |   |__anterior pupal spiracle 84 rec.
                                            |   |__cephalic tracheal branch primordium
                                            |   |__embryonic/larval cerebral tracheal anastomosis 6 rec.
                                            |   |__larval dorsal tracheal anastomosis 1
                                            |   |__larval tracheal branch of Tr1(+) 32 rec.
                                            |   |__larval ventral tracheal anastomosis 1 1 rec.
                                            |   |__pupal dorsal tracheal branch 1
                                            |   |__pupal ganglionic tracheal branch 1
                                            |   |__pupal spiracular tracheal branch 1
                                            |   |__pupal ventral tracheal anastomosis 1
                                            |   |__pupal ventral tracheal branch 1
                                            |__tracheal metamere 2 24 rec.
                                                |__adult spiracular tracheal branch 2
                                                |__embryonic/larval dorsal tracheal branch 2 8 rec.
                                                |__embryonic/larval ganglionic tracheal branch 2 8 rec.
                                                |__embryonic/larval spiracular tracheal branch 2
                                                |__embryonic/larval tracheal transverse connective 2
                                                |__larval dorsal group tracheal branch 2
                                                |__larval dorsal tracheal anastomosis 2 2 rec.
                                                |__larval fat body tracheal branch 2
                                                |__larval lateral E tracheal branch 2
                                                |__larval lateral F tracheal branch 2
                                                |__larval lateral H tracheal branch 2
                                                |__larval ventral tracheal anastomosis 2 1 rec.
                                                |__non-functional pupal spiracle 2
                                                |__pupal dorsal tracheal branch 2
                                                |__pupal ganglionic tracheal branch 2
                                                |__pupal spiracular tracheal branch 2
                                                |__pupal tracheal transverse connective 1
                                                |__pupal ventral tracheal anastomosis 2
                                                |__pupal ventral tracheal branch 2
                                                |__visceral tracheal branch 2