Calosoma scrutator

Calosoma scrutator, also known as the fiery searcher and caterpillar hunter, is a species of ground beetle belonging to the genus Calosoma, subgenus Acalosoma. This beetle can be as large as 35 mm long. The distribution of this species is relatively widespread, but it is nonetheless common in North America. The adult beetle is known to excrete a foul-smelling oil when it is handled. The oil has been described as smelling similar to rotten milk or rancid olive oil.