The mites feed on the adult's body fluids and return to the water after obtaining sufficient food. As the adult Odonate emerges from the last larval skin, the mites attach onto the soft body of the new adult via its piercing mouthparts. The female mite lays its eggs in the water and as soon as they hatch, the young mites search for an Odonate larvae that is just about to emerge. Water mites are common parasites of Odonates. Some wasps capture Odonates, kill them, and deposit their eggs in the dead insect (Berger and Hansen, 2004). However, certain wasp species do oviposit in Odonate eggs, which the wasp larvae feeds on after it hatches (Santolamazza et al. Some nymphs travel quite far from the water.Yellow bittern feeding on a damselflyPermission pendingBy Chris Lee, Bird Ecology Study GroupĢ) Parasitoids and parasites In general, little is known about parasitoids of Odonate eggs partly owing to the fact that Odonate eggs are often well concealed amongst the vegetation or found submerged in water. When it is finally ready for its last molt, the larva crawls out of the water and grabs hold of a plant stem or other surface. The closer to adulthood the nymph is, the fuller the wing pads appear. In the coldest regions of their range, dragonflies may remain in the larval stage for several years.ĭuring the final few instars, the dragonfly nymph begins to develop its adult wings, although they remain tucked inside wing pads. In warmer climates, the larval stage may take only a month, with the nymph growing rapidly. Odonate nymphs have modified lower lips, which they can thrust forward in a split second to grab a passing tadpole, arthropod, or small fish.ĭragonfly nymphs molt between 9 and 17 times as they grow and develop, but how quickly they reach each instar depends greatly on the climate. Other species hunt actively, sneaking up on prey or even swimming in pursuit of their meals. Some species lie in wait for prey and hide by either burrowing in the mud or resting within the vegetation. Like adult dragonflies, the nymphs are predators. Damselfly nymphs swim by undulating their bodies. When they expel the water, they are propelled forward. Dragonflies pull water into their rectums to respire. Damselfly gills are located at the end of the abdomen, while the gills of dragonfly larvae are found inside their rectums. All dragonfly and damselfly nymphs are aquatic and remain in the water until they are ready to molt into adulthood.ĭuring this aquatic stage, odonate nymphs breathe through gills. This immature stage looks quite different from the adult dragonfly. If the prolarva hatches from an egg that was deposited on the soil, it will make its way to the water before molting.ĭragonfly larvae are also called nymphs or naiads.
In dragonflies and damselflies, a prolarva hatches from the egg and quickly molts into the true larval form. In some species, eggs may hatch in just a few days, while in others, the eggs may overwinter and hatch the following spring. Dragonfly conservationists are concerned that manmade objects may be putting some odonates at risk of decline because female dragonflies have been known to deposit their eggs on solar panels or car hoods instead of in ponds or streams.Įgg hatching varies considerably. Unfortunately, dragonflies cannot always distinguish the surface of a pond from other reflective surfaces, like the shiny finishes on cars. Exophytic ovipositors include clubtails, skimmers, emeralds, and spiketails. Dragonflies that oviposit directly into the water may produce thousands of eggs. The eggs sink to the bottom or fall onto aquatic vegetation. Others dip their abdomens into the water to release their eggs. Some species fly low over the water, dropping eggs at intervals into the water. In exophytic ovipositors, the females extrude eggs from a special pore on the underside of the abdomen.
These dragonflies deposit their eggs on the water's surface, or in some cases, on the ground near the pond or stream. Some dragonflies are exophytic ovipositors. In some species, the female will briefly submerge herself in order to oviposit in a plant well below the water's surface. Endophytic ovipositors include all damselflies, as well as petal tail dragonflies and darners. The female typically slits open the stem of an aquatic plant just below the waterline and places her eggs inside the stem.
Most odonate species are endophytic ovipositors, meaning they insert their eggs into plant tissues using well-developed ovipositors. Mated dragonflies and damselflies deposit their eggs in, on, or near the water, depending on the kind of odonate.
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