Dragonflies are recognizable insects, known for their iridescent wings and remarkable aerial agility. They represent an ancient lineage, having existed on Earth for hundreds of millions of years. Despite their ubiquity, the life cycle of a dragonfly remains a mystery to many, especially the identity of the young. This phase is spent entirely underwater, leading to confusion about what the baby dragonfly is actually called.
The Specific Name for Dragonfly Young
The life cycle of a dragonfly involves incomplete metamorphosis, which has three distinct stages: egg, immature aquatic form, and adult. The general term for the immature stage of an insect undergoing this transformation is a nymph. Because dragonflies, damselflies, and mayflies spend this stage in water, entomologists use the specialized term naiad to distinguish them from terrestrial nymphs. The term “naiad” comes from Greek mythology, referring to a water spirit, reflecting the young dragonfly’s habitat. This aquatic stage is where the dragonfly spends the vast majority of its life, lasting from a few months to several years depending on the species.
Life Underwater: Appearance and Diet
The dragonfly naiad is a formidable, though often camouflaged, predator dwelling among the sediment and vegetation of freshwater bodies. Unlike the colorful adult, the naiad is typically a dull brown, green, or black color, allowing it to blend into its surroundings on the pond floor. It possesses six legs and developing wing pads on its back, but it is wholly wingless and much thicker-bodied than a damselfly naiad.
The naiad’s method of respiration involves drawing water into a chamber at the end of its abdomen, where internal gills are located. This system allows the naiad to breathe effectively while submerged, often remaining still while waiting for prey. When threatened, the naiad can forcefully expel the water from this chamber, using the rapid jet of water as propulsion to escape.
The naiad is a voracious hunter, consuming any aquatic life it can overpower, including insect larvae, small fish, and tadpoles. Its primary hunting tool is a specialized lower lip, the labium, which is folded beneath its head like a mask. When prey comes within range, the labium is instantaneously shot forward on a hinged joint. This lower lip is equipped with hooks or pincers to grasp and secure the victim before retracting it back to the mouthparts.
Emerging from the Water: The Final Molt
The duration of the naiad stage is influenced by factors like water temperature and food availability, leading to many molts as the insect grows. Once it has reached its full size and the internal transformation is complete, the naiad begins the final transition to its adult form. This emergence is triggered by environmental cues like day length and temperature, signaling that it is time to leave its aquatic home.
The final step requires the naiad to climb out of the water, ascending a reed, rock, or vegetation to find a secure, dry perch. It clings tightly to this surface, and the skin along its back splits open, a process known as the final molt. The adult dragonfly slowly pushes its head, legs, and thorax out of the old larval skin, which remains behind as a dried husk called the exuvia.
The newly emerged adult, often called a teneral, is initially soft-bodied, pale, and unable to fly. It must pump fluid into its crumpled wings and abdomen to expand and harden them before taking its first flight. This entire process, from climbing out of the water to achieving flight, is a vulnerable period that can take several hours. After this, the airborne adult dragonfly begins its short, final chapter.