Scent-defense
Guides
Arocatus melanocephalus
elm seed bug
Arocatus melanocephalus, commonly known as the elm seed bug, is a true bug in the family Lygaeidae. Native to Europe, it has been introduced to North America in the 2000s and has become a notable nuisance pest in urban areas. The species is distinguished by its dark red body, black head, and characteristic M-shaped spot on the pronotum. Adults produce a strong, unpleasant odor reminiscent of bitter almonds from metathoracic scent glands. Unlike many Lygaeinae species, it has limited ability to store cardenolides.