No. See David Jewitt's Kuiper Belt page and follow the link "The 1000 km Scale KBOs". He lists all of the large KBO's, and Eris remains in first place above Pluto (2005 FY9 was already known before anyone knew how large Eris was). You can also check Mike Brown's page at Caltech. If there is a big KBO discovery, it will show up on one or both of those pages fairly quickly.

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