The third body of YR is the Council of Royal and Select Masters, or Council of Cryptic Masons. It is chronologically out of order and comes before the building of King Solomon’s Temple. It would not make sense to confer the degrees upon a non-mason so they are given after the Royal Arch degree in the US.
Missing from the diagram, except for the name ant symbol of a trowel in a triangle, is the Super Excellent Master's degree. This degree takes a cast of over 50 and is rarely performed. I have seen it once, at my own conferral, and it was epic. Longer degree in its full form.