Introducing the Mango Nectarine
The skin itself is thick, and there's a buttock-type crack running from the bottom to the top of the fruit on only one side.
When you bite into it, the flesh is almost orange, fairly firm, and quite sweet. Yes, it does taste something like a combination of plum and mango flavors.
The unique fruit arose as a hybrid of two naturally occuring variations that spontaneously arose in the California fruit fields. The husbandman knows how to take advantage of these freaks of nature, called "sports," by grafting them onto normal trees and seeing if they will propagate. A sport is thought to occur only once per season for every 40 acres of fruit trees.
Apparently, nectarines were largely green- and white-fleshed up until the 1940s, when growers started to favor orange-skinned nectarines with darker, creamier flesh.
Find them at Citarella stores, and elsewhere in town.
Follow me on Twitter: @robertsietsema.