Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5b3e53315f842081aebf508beec05ae83760c0750fe4ee6ae64c46418d26ddf' 
  AND token = 'szatBIdhXUTbVRtRfBSm12mCOaPrw8F0OJV63jESn74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE								Impossible WHERE noticed after reading const tables