Gnat Ogre - prey (IMAGE) University of Minnesota Caption The Gnat Ogre (Holcocephala fusca) is a predatory robber fly that grabs other insects out of the air, catching them with extreme precision. This particular fly holds a small rove beetle as prey on its proboscis. Credit S T Fabian, Fly Systems Laboratory, University of Minnesota. Usage Restrictions Copyright S T Fabian License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.