SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df5f1420bc6bb754972ae37782637deeaf616a36fdaa69bfbc395e6e7d9242ee' 
  AND token = 'oWJJuy+82FQDSysd3yD8cr82gDmTGKF5Ti6eGkCls8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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