Dragonhunter

Hagenius brevistylus — the dragonhunter — is one of the largest dragonflies in eastern North America and the apex aerial predator of NA freshwater dragonfly communities. The species is one of about 100 species in family Gomphidae (the clubtail dragonflies — distinguished by enlarged 'club-shaped' final abdominal segments) and is the only species in genus Hagenius. The species is widespread across all of eastern North America from southern Canada south through the eastern US to Texas. Adults are 8-9 cm body length, 11 cm wingspan, with the species' diagnostic feature: the LARGEST OVERALL SIZE of any clubtail dragonfly in North America (substantially larger than other gomphids like Gomphus, Stylurus, etc.) combined with massive enlarged terminal abdominal segments forming a dramatic 'club' shape, dark brown-and-yellow body coloration, and bright greenish thoracic stripes. The species lives up to its common name as the APEX DRAGONFLY HUNTER of eastern NA aquatic ecosystems — dragonhunters REGULARLY HUNT AND EAT OTHER DRAGONFLIES as their primary prey. The hunting behavior: dragonhunters perch on prominent waterside substrates (logs, exposed branches, dock pilings) and watch for passing dragonflies; when prey is spotted, the dragonhunter launches into a high-speed pursuit flight, intercepts the prey mid-air, and seizes it with the powerful raptorial legs. Documented prey include EASTERN PONDHAWKS (themselves aggressive predators that eat other dragonflies), COMMON WHITETAILS, TWELVE-SPOTTED SKIMMERS, FLAME SKIMMERS, OTHER GOMPHID CLUBTAILS, and various damselflies. Dragonhunters are unique among gomphid dragonflies in their willingness to hunt large prey of similar size to themselves — most gomphids hunt small flying insects like midges and gnats. The species also famously hunts MONARCH BUTTERFLIES (one of the few documented dragonfly predators of toxic monarchs — the dragonhunter's powerful jaws can crush monarch wings before the butterfly can deploy its chemical defense), and even other large arthropods including BUTTERFLIES, MOTHS, BEES, and WASPS that come to nectar at waterside flowers. The species is widespread but uncommon across eastern NA — populations are locally abundant at well-vegetated medium-sized streams and rivers but absent from many similar habitats (the reasons for the patchy distribution are not fully understood). Naiads develop in stream and river substrates over 2-3 years and are equally voracious aquatic predators. The species is harmless to humans (no sting, no bite) but is the most-feared aerial predator in eastern NA dragonfly communities.