Picture card Welshman turned up after king (5)
I believe the answer is:
knave
'picture card' is the definition.
(knave is a kind of picture card)
'welshman turned up after king' is the wordplay.
'welshman' becomes 'Evan' (common Welsh name).
'turned up' shows that the letters should be reversed in order.
'after' says to put letters next to each other.
'king' becomes 'K' (chess abbreviation).
'evan' backwards is 'nave'.
'nave' put after 'k' is 'KNAVE'.
(Other definitions for knave that I've seen before include "Jack - rotter" , "Jack - the cad!" , "Dishonest man; jack" , "Villain - jack" , "Honour" .)