Today, I saw, for the first time, yams at Walmart (in Idaho), which were not sweet potatoes. They were probably Dioscorea, by the look of them, but I'm uncertain. Definitely nothing I've ever seen in the grocery store before. Exciting.
This is in the Monocots forum because the alternatives to sweet potatoes that I know it could be are all Monocots.
yam_dioscorea_sweet_potato