Dragonflies Are Not What You Think

Dragonflies undergo incomplete metamorphosis, distinct from the complete metamorphosis of butterflies, beetles, and wasps that includes egg, larva, pupa, and adult stages.

Dragonfly nymph mouthparts contain two distinct catapult systems: the pre-mental catapult and the post-mental catapult. These structures store and release mechanical energy similar to engineered catapults.

Dragonfly nymphs are the only insects known to use jet propulsion for locomotion. Scientists observed that certain larvae eject water jets from their rectal chamber during prey capture, creating a synchronized strike-and-propulsion system.

Among approximately 7,000 dragonfly species worldwide, all begin life as aquatic nymphs with diverse morphologies. Four main types exist: claspers with slender bodies and long legs, sprawlers with flattened bodies, hiders with compact camouflaged bodies, and burrowers with cylindrical bodies.

Dragonfly nymphs possess an extendable labium, often called a mask, consisting of four movable elements: the post-mentum, prementum, and two labial palps that fold up and interlock at rest.

All dragonfly nymphs possess rectal gills that enable aquatic respiration through a process called rectal ventilation, commonly known as butt breathing. Burrowing nymphs feature specialized tube butts that extend into the water column.

Cornell University researchers led by Chris Row discovered that dragonfly nymphs possess a trileaflet anal valve resembling human heart valves, with three independently controllable leaflets that block one-third of the valve opening.

Cornell University biomedical engineering researchers propose novel prosthetic heart valve designs inspired by dragonfly nymph anal valves. Three human heart valves possess trileaflet structures similar to these insect valves.