Well, that’s what they’re calling this painting. Based on this portrait they’re thinking that maybe da Vinci painted the Mona Lisa in variety of ways. They’re saying this even though the model doesn’t bare a resemblance to the Mona Lisa:

The work, which documents suggest was at least based on never-seen similar work by da Vinci, is now on exhibit at the Museo Ideale in the Tuscan town of Vinci, where da Vinci was born in 1452.
[…]
The lady in the portrait does not exactly resemble the original Mona Lisa, but there is little doubt it has parallels with the painting hanging at the Louvre museum in Paris.
“The frontal look, the position of the hands, the spatial conception of the landscape, with columns at the sides, show a clear link with the Mona Lisa’s iconographic theme,” Alessandro Vezzosi, director of the museum, told Discovery News.

Here’s the original so you can compare but I’m not seeing the similarity beyond a superficial posing-the-model-in-a-similar-manner-with-a-background way:

But of course it’s more exciting to say that this obscure painting has something to do with the Mona Lisa. Don’t we like to link all kinds of obscure theories to that painting?