SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47ff61d5b441df1ac9f25caac09959835d9dc138e26cd0e36f3fdb50f88db56f' 
  AND token = 'EhgjNgxJ1gQR0Nkyp2aZ89fT4+efWfEct5cYQwbYPpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

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