Length: 15.5-23.5 mm
The common name refers to similar-looking Ground Beetles that defend themselves by ejecting a spray of hydroquinone and hydrogen peroxide, in a visible cloud and with an audible pop.
These Galerita beetles are not entirely "false" when it comes to bombing. Galerita Ground Beetles also have a chemical spray, in their case composed primarily of formic acidthe same compound used defensively by ants.
The easiest way to separate False Bombardier Beetles from "real" Bombardier Beetles is that the False Bombardier Beetles have a dark head.
West Virginia is home to two species of False Bombardier Beetle, Galerita bicolor and G. janus. The two are quite similar and are best separated by comparing the head shape. Behind the eyes, the sides of the head are somewhat rounded in G. janus, and oblique in G. bicolor. Another difference is that the fine hairs on the pronotum are laying down and pointed toward the rear on G. janus, and erect on G. bicolor. Downie and Arnett suggest that G. janus has "blacker and rougher" elytra than G. bicolor. There is no appreciable size difference between the two species.
These two species of Galerita are pretty common in West Virginia, either walking in the open, or under the protection of some cover. The beetles shown here were photographed in a the crevice between two Sugar Maple trunks in Upshur County in mid-April.
Insects of West Virginia