Aphelinidae
Important members are:
Encarsia formosa -- Parasitic Wasp of the whitefly.
<table border='0' cellpadding='0' cellspacing='0' width='468' height='268'> <tr> <td> <a href='http://www.amazon.co.uk/exec/obidos/redirect-home/ref=nosim?tag=martinlee' target="_blank"> <img src="http://images-eu.amazon.com/images/G/02/associates/recommends/default_468x268.gif" width="468" height="268" border="0" access="regular"></a></td> </tr> </table>