SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d7ea830891ada4db2e1940c4fd211d759be3143cb23ad539ba5455827dcf7e8' 
  AND token = 'tyCA2fSYs49VY9Y4Z0Adry5hvRmDnDU/c0ahQYWgYog=' 
  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