Metrius contractus - Bombardier Beetle
Oregon, USA

photograph © Alex Wild 2006

The bombardier defensive mechanism- an explosive mix of chemicals expelled from the rear of the beetle- is found in at least two different groups of ground beetles.  The most well-known bombardiers are the colorful Brachinus species, but Metrius and related paussine beetles possess a similar behavior. 

USA, Oregon.

This image is copyrighted by the photographer and cannot be used without permission. To obtain permission to use this image, please email Alex Wild. (alwild (at)  Most of the photographs on are reduced from their original size and compressed for more efficient web transmission.  In some cases, higher quality versions are available.

This image was captured with a Canon EOS 20D, with a Canon 65/2.8 MPE 1-5x Macro lens.