Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb6d3c557f94f7d75957a3f6f63f2ffd472230cd7d837574cf76c01d0534b5b4' 
  AND token = 'MpqMRti3xR8HZJbvwFQwZu0XGXLU25bMm7kRuZyapH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

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