Shield bugs (Pentatomidae) are a family of true bugs easily recognized by their broad, flat, triangular bodies that resemble a medieval knight’s shield. They are famous for their piercing-sucking mouthparts, their vibrant variety of colors, and a specialized defense mechanism: thoracic glands that emit a pungent, foul-smelling liquid when threatened. I spotted this large (2,5cm) shield bug (Brachystethus improvisus) while exploring the botanical garden of Puyo, Ecuador. Its bold, high-contrast black and red coloring serves as a biological “stop sign” to predators like birds. Known as aposematic coloration, this vivid visual display warns potential hunters that the bug is highly toxic, unpalatable, or tastes absolutely terrible, allowing this shield knight to roam the tropical foliage in peace.