Detail of the shields of a wintering Carabus violaceus. The individual was hidden under the bark of a log. This specimen has a quite unusual coloration: the greenish colour found on the entire shields is uncommon. Most of the individuals have a bluish or purplish thorax and have only the fringes of their shields coloured (mostly often purplish or violet).

Carabus violaceus purpurascens or Megodontus violaceus purpurascens is considered by some authors (Rautenstrauch) as a separate species, 'Megondontus purpurascens', which occurs in the Western part of Europe. In Turin et al., 'purpurascens' is considered as a subspecies of Megodontus violaceus or Carabus violaceus.