SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '477e4905363fb9daab34950694deafcbf22179bd4c42d8b3b386cf6fd307ef42' 
  AND token = 'MxV7eTanka9qIoOr534ku/Unbk3NrOO2HH4eH+HiEYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

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