The western conifer seed bug (Leptoglossus occidentalis), generally abbreviated as WCSB, is a species of true bug (Hemiptera) in the household Coreidae. It is native to North America west of the Rocky Mountains (California to British Columbia, east to Idaho and Nevada) but has in current times expanded its range to eastern North America, to include Ontario, New Brunswick, Nova Scotia, Maine, Pennsylvania, New York, Connecticut, Massachusetts, and New Hampshire, and has turn into an unintended launched species in parts of Europe and Argentina. This species is a member of the insect family Coreidae, or leaf-footed bugs, which also includes the similar Leptoglossus phyllopus and Acanthocephala femorata, each known as the Florida leaf-footed bug”. Western conifer seed bugs are typically colloquially referred to as stink bugs. While they do use a foul-smelling spray as a protection, they don’t seem to be categorised within the stink bug household Pentatomidae. In Chile, it has been confused with kissing bugs (Triatominae), causing unjustified alarm.