Herbert‘s and Breviceps Giant Water Bugs
Hemiptera: Belostomatidae Abedus herberti herberti Hidalgo and Abedus breviceps Stål
History and distribution
Herbert’s giant water bug is found in lower Grand Canyon in streams within the ancient drainage of the early Cenozoic “California River”, a river that flowed east and north across the northwestern corner of Arizona. Herbert’s giant water bug is widespread through the Southwest. In contrast, the abedus water bug is found only in a single stream in central Grand Canyon, the only population of that species on the southern Colorado Plateau.
These are two of three giant water bug species known from Grand Canyon, all of which occur in desert spring-fed streams, and all of which are aquatic predators. Behavioral observations on abedus water bugs in southern Arizona revealed that it senses on-coming flashfloods, and climbs out of the water and above the flood waters to avoid the scouring effects of summer floods.