prothoracic femoral chordotonal organ prothoracic femoral chordotonal organ 2 VFB:FBbt_00004273 FBbt:00004273 One of the small chordotonal organ of the adult prothoracic femur. It is located in the center of the femur and has around 14 scolopidia. Distally, the scolopidia are more scattered than the prothoracic femoral chordotonal organ 1, with a majority of them connected to the femoral muscle membrane. fly_anatomy.ontology