Spartan queen of myth (4)
I believe the answer is:
leda
'spartan queen of myth' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for leda that I've seen before include "small satellite of Jupiter" , "Zeus turned into a swan to seduce her" , "- - and the Swan (mythology)" , "She was seduced by Zeus disguised as a swan" , "Mother of Helen and Pollux" .)