In which apparition is The Virgin Mary depicted holding a serpent?

Answer 1

None! There is a description crushing the serpent under her heal in the New Testament

Answer 2

The only one that mentions anything close to this imagery is in the book of Genesis.
There is an Old Testament passage in the Bible which has the promise that God had made in Genesis 3:14-15 "And the LORD God said unto the serpent … I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel."

In the 1500's,something else happened which involved the Virgin Mary and the serpent.
The Aztecs worshipped an evil stone "serpent god" that demanded human sacrifice. It was extremely difficult to win souls for Christ from these bloodthirsty savages. However, with God all things are possible.
Our Lady appeared to a humble Aztec Indian convert by the name of Juan Diego in 1531. When asked her name by Juan Diego, at the request of the local bishop, Our Lady's response, in the Aztec language, included the words "te coatlaxopeuh" (pronounced: "te quatlasupe") and meant "one who crushes the head of the stone serpent."

To Juan Diego and his fellow Aztecs, this revelation had great meaning, coupled with the miraculous image of Our Lady standing on top of a "crescent," the symbol of this evil serpent god. A tidal wave of conversions to Catholicism ensued.

However, Bishop Zumarraga, who was from Spain, made what was no doubt a "heavenly mistake" that one day may lead to the mass conversion of Moslems.
To the Bishop's Spanish ears, Our Lady's Aztec name of "Te Quatlasupe" sounded just like the name of the revered Madonna from Spain with the Islamic name, "Guadalupe." Hence, the bishop named the Mexican Madonna "Our Lady of Guadalupe." It is interesting that the "crescent" is also the symbol for Islam and that America's Shrine to Our Lady has an Islamic name.

In the fullness of time, we can be sure that Almighty God knew that the Islamic religion would pose a serious threat to Christianity.

Answer 3

I don't recall any of the pictures/statues of the Virgin depicting her HOLDING a serpent.
She is always depicted crushing a serpent under her feet.