SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dc8e9cfd9bbedcd234e3ca7df01e9ca25ac0ca480226ad7f3cb03e30749601c' 
  AND token = 'aXni6oaGZHV8Q7BQHDFU0l+HmTSwBwH6wcJMvz0q0hY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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