Look at the semantic table, second column. It has both the realm and duchy, but the column header only says 'realm'.
This is because membership in both the duchy and the realm is denoted by the "part of" property. Tom has been adamant that these not be split, and that we don't make a "duchy of" property, or a "realm" of property.. The problem is that we have never been able to separate what each is talking about. It's easier of you selected based on "part of::Terran". (Well, it used to be, I guess, but now you can actually have a duchy named "Terran", like Iashalur has a duchy of Iashalur... What a mess.)
Given how the new duchies work, and the fact that you can have arbitrary numbers of duchies with arbitrary names, the external data feed and semantic properties may need to be revisited. There are already a lot of assumptions that we used to make that are no longer true.
