Cranach

"In january 1508 Frederick awarded the Heraldic Letter to Cranach, permitting him to bear a coat of arms with the painter's personal device: a crowned serpent with wings holding a ruby ring in its mouth.

Adopted as a symbol of Cranach's artistic identity, the winged serpent appears on most of the paintings produced by the artist and his workshop, although the emblem's configuration varied over the course of his career."