The Matador Bug and Several Related Leaf-footed Bugs (Hemiptera: Coreidae) Accumulate Cyanogens From their Host Plants.

Cyanogenic compounds provide potent defenses to herbivorous insects, yet few species are known to acquire them from their food. Matador bugs, Bitta alipes (Hemiptera: Coreidae), have brightly colored signals that deter avian predators and are specialists of cyanogenic Passiflora plants. It is unknown whether these insects accumulate cyanogenic compounds. We document the first evidence of cyanogen accumulation in matador bugs. However, the presence and concentration of cyanogens depended on the Passiflora species from which insects were feeding. Further, three related species of inconspicuous Coreidae, and their Cactaceae and Aquifoliaceae host plants, also contained cyanogenic compounds. In all coreid species, cyanogen concentrations detected would make them unpalatable, or even lethal, to vertebrate predators. We report the first evidence of cyanogenic compounds in the Coreidae, doubling the number of species known to accumulate cyanide in the Hemiptera. Cyanogen accumulation may be more common amongst hemipterans than previously thought, prompting studies to examine the mechanisms of secondary chemical accumulation and evolution of aposematism.