Thanasimus formicarius

The ant beetle (Thanasimus formicarius), also known as the European red-bellied clerid, is a medium size insect, rather soft-bodied, with strong mandibles that can tear between the hard sclerotized integument of bark beetles. Larvae and adults are common predators of bark beetles in Europe. The adults overwinter at the base of conifers, rarely of deciduous trees. They emerge in the spring and fly to lower parts of trees to hunt bark beetles. Their common prey are pine bark beetles Tomicus piniperda and T. minor, and the European spruce bark beetle, Ips typographus. Often they are seen waiting their prey on the bark of fallen pine or spruce trees. Both ant beetles and bark beetles are attracted to monoterpenes from the damaged areas of the fallen trees. Stacked wood is especially attractive due to the monoterpene volatiles. The ant beetles are also attracted to specific pheromone components of bark beetles therefore they often fall into bark beetle pheromone traps. The larvae enter the scolytid galleries and feed on the immature stages of the bark beetles. The larvae grow very slowly, spending two years in the larval stage, and pupate in the fall in niches in the outer bark. Adults of T. formicarius live 4 to 10 months. Males and females mate repeatedly, with many different partners throughout the season. Mating is short, and the copulation precedes a chase and a firm grasp of the female with the male mandibles on her pronotum.