Calosoma retusum, the blunt-toothed caterpillar hunter, is a beetle of the family Carabidae.
Calosoma retusum reaches about in length. This species usually has a bright metallic dark green or bronze green coloration, sometime with bluish reflections. The borders of the pronotum are rounded and raised. Elytra are striated, with large punctures. These beetles are voracious consumer of caterpillars, so they are considered beneficial insects for the agriculture.
This species occurs in southern Brazil, Uruguay, Argentina, Bolivia and Peru.