Armor Stand not detectable in item form

Armor Stand not detectable in item form.  EXP: after an armor stand is broken or is thrown on to the ground as an item, the command: /testfor @e[type=item, name=armor_stand, r=20] returns no result.  Expected behavior would be the same as paintings. Breaking a painting drops the painting as an item that can be detected using /testfor @e[type=item, name=painting, r=20].