R. grandis spends its whole life in association with its prey, living underneath the bark of spruce trees.

[2] During the twentieth century, D. micans has been steadily increasing its range, and R. grandis has tended to follow.

The effects of the predator were apparent when both spread into Germany around the beginning of the century, and after D. micans had invaded Georgia in the 1950s, the first programme for its biological control involving R. grandis was established there in 1963.

Since then, rearing of the predatory beetle has been undertaken in Georgia, using cut logs infested with D. micans.

An attempt to do this was made when small numbers of the predator were imported from Belgium and released in Louisiana in 1988.