SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c92cb8a39778f4fd76c7511f86233461a1186daefa475671eb6d09c43c10165' 
  AND token = '4XUefT/XEzC51GJBlupKtveNF532pWbTv+therD2BY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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