Laemostenus janthinus is a species in the beetle family Carabidae.

[1][2] Laemostenus janthinus can reach a length of about 14–17.5 millimetres (0.55–0.69 in).

[3] It is a nocturnal predator of other small arthropods.

This species can be found in Austria, Bosnia, Croatia, France, Italy, Poland, Slovenia and Switzerland.

[4] This species inhabits forests and Alpine prairies at an elevation of 2000–2400 meters above sea level.