What about the Falklands?
Well I guess we could count that too, if we count Falklands as part of South America. I'm guessing that the UK wouldn't want it to "count" as part of the continent because it's not actually joined. But plenty of islands in Europe are counted as part of Europe, and Japan, Taiwan and Philippines are all part of "Asia", so there's no much of a consistent reason not to count Falklands as part of South America. It's certainly part of the "Americas", and if you split that into North, Central and South Americas, it's clearly in the South.
EDIT: To give an idea of the under-reporting about UNASUR, which is one of the biggest political developments in the Western Hemishpere in decades, this is the nytimes seach for all articles containing "unasur":
http://query.nytimes.com/search/sitesearch/#/unasur/since1851/allresults/1/allauthors/oldest/Exactly 16 hits over 10 years. So Unasur gets mentioned, briefly, in one article every 6 months in the New York Times. Note also that the nytimes completely stopped reporting on Unasur the very day that the treaty was ratified, and there's a
4-year gap in which the term "unasur" was basically verboten from nytimes coverage from 2008 to 2012. And up until 2008 they were reporting on Unasur as "like the EU, but for South America", but the post 2012 articles are trying to sound as dismissive as possible, or they include mentions of Unasur purely by accident, or snuck in sneakily by opinion piece writers:
2012 opinion piece on Ecuadors military history. The writer sneaks a mention of what Unasur is into the bottom of the footnotes (footnote 17).
2012 Story about political crisis in Paraguay mentions Unasur as a "political bloc" without any context.
Similar article 1 day later, unasur "regional bloc".2012 Assange story, off-hand reference to unasur as some vague thing that "including most states" on the continent, without mention that's because the only non-member is part of France.
2012 accidentally mentioned Unasur because it was part of Christina Kirchner's election victory tweet, in Spanish.
2012 mention of Venezuela elections, merely mentions Unasur as an "organization" without any context.
After that, there are basically 5 mentions of Unasur from 2013-2016, so basically one brief mention every year or so, and they're even more dismissive of it than before. The only mention in the last two years is a June 2016 one that basically labels UNASUR as lackeys of those Venezuelan commies, without any other context. So they're getting worse at reporting this, if anything.
Meanwhile, "Kardiashian" gets 1086 hits, in the same time period.
http://query.nytimes.com/search/sitesearch/#/kardashian/from20070101to20161212/allresults/2/allauthors/oldest/