Did Leonardo da Vinci paint two Mona Lisas? Where are they?

Source: St Petersburg. Hermitage, Russia.

While overall similar, there are differences in the shape of the face, the background and other details.

For the one below, art experts suggest that it contains touches indicating that Leonardo contributed to it.

NASA Discovers Strange X-Shaped Structures in Earth’s Upper Atmosphere - Indian Defence Review

Then there are the ‘meza nuda’ paintings from his workshop, often referred to as Monna Vannas.

Donna Nuda:

Source: Louvre, Paris, France.

Why do people believe that global warming is man made?

Source: Chantilly, Musée Condé, France.

Evidently there was a market for erotic paintings. The American art historian David Brown, curator of Italian Renaissance paintings at the National Gallery of Art in Washington, has suggested that da Vinci painted a saucy parody of the Mona Lisa for his patron Giuliano de Medici, and that the Salai version is a copy.

Obviously, the original Mona Lisa also inspired some cheeky versions of her.

Win a signed pink cycling jersey of Giro winner Simon Yates - Team Visma

There is only one Mona Lisa, at the Louvre, fully credited to Leonardo. However, there are several Mona Lisa look-alikes from his studio, some of them quite saucy. The one most similar to the Louvre one is the Prado Mona Lisa, a copy made simultaneously in Leonardo's workshop while he painted the Mona Lisa, probably made by an apprentice(s):

Another version of the above exists, attributed to Salaj:

La Joconde nue:

Why are black people seen as scary or a threat to some people?