Okay, I found a Brazilian daikon at the organic farmers' market. You can tell it's Brazilian Japanese because of the black-and-white wave mosaic pattern on the ground and the Havaiana flip-flops. This is not a yacon (Cf. my Glória farmers' market gaffe). I picked it up at the veggie stand and, playing it safe, asked, "What's this?" The farmstand woman was like, "Duh, it's a daikon" (pronounced the same way in Portuguese) and I felt properly shamed for not recognizing my own kind.