A previously unknown portrait of what could have been William Shakespeare's gay lover has been revealed.

The miniature portrait, painted on the back of a playing card, could be an intimate painting of the playwright's patron and paramour.

Dr Elizabeth Goldring, an art historian and honorary reader at the University of Warwick, revealed the 16th-century painting was probably a love token with great emotional significance to the owner.

The portrait of an androgynous figure depicts Henry Wriothesley, the third Earl of Southampton.

Originally part of a private collection held by a branch of his family, it was recently sold to an unnamed party.