SRD:Giant Bombardier Beetle

=GIANT BOMBARDIER BEETLE=

These creatures feed primarily on carrion and offal, gathering heaps of the stuff in which to build nests and lay eggs. A giant bombardier beetle is about 6 feet long. Giant bombardier beetles normally attack only to defend themselves, their nests, or their eggs.

Acid Spray (Ex): When attacked or disturbed, the creature can release a 10-foot cone of acidic vapor once per round. Those within the cone must succeed on a DC 13 Fortitude save or take 1d4+2 points of acid damage. The save DC is Constitution-based.

See Wikipedia Entry: Bombardier beetle