They were much more diverse in the past, with dozens of described species from the Mesozoic.

[1] Their habits are similar to those of the ground beetles; they are usually found in the leaf litter of conifer forests, and are thought to be mostly predators and scavengers, active during the day (diurnal).

[2] Recent molecular phylogenies have recovered as the sister group to the clade Carabidae+Cicindelidae as part of the Adephaga subgroup Geadephaga.

[3][4] The earliest fossils known of this family are of the genera Petrodromeus, Permunda and Apermunda from the Permian-Triassic boundary of Russia around 252 million years ago.

The two subfamilies are distinguished by the shape and position of the sclerites that are jointed to the mesocoxae (the section where the middle pair of legs joins the body).