Dragonfly larvae images11/9/2023 To accomplish this, the nymph finds a sturdy plant stalk or other object near the water’s edge to climb. Once their final molt is complete, they are ready to hatch out into full-fledged dragonflies. It is so reminiscent of the extendable mouth of the titular Alien creature in classic film series, many wonder if that terror was inspired by these miniscule macroinvertebrates. In a flash they can extend their lower mandible, grab prey with attached pincers, and bring it directly to its mouth for a tasty meal. A wriggling mosquito larva, newly hatched tadpole, tiny fish, and other insect larvae hardly stand a chance against a jet-propelled shadow darner nymph. These nymphs are incredibly adept at catching prey. Once they hatch they go through anywhere from 6 to 15 molts (depending on species) growing in size each time. In temperate areas, they hatch in spring from tiny eggs their mothers meticulously deposited around the edges of ponds, on aquatic plants, or directly in the water the previous summer or early fall. Adults live for only about one month while the pond-bound larval stage of dragonfly and damselfly species range anywhere from several months to several years. Though best known for their aerial abilities, dragonflies actually spend the majority of their lives not in the air, but under water. Though their morphology hasn’t changed much over those unfathomable reaches of time, today’s dragonflies reach a mere fraction that size. Some had an ~2.5 foot wingspan, putting them on par with today’s Pileated Woodpeckers. The largest of them all, and still to this day the largest that has yet been found in the fossil record, were the extinct dragonfly ancestors known as griffenflies. Insects abounded, and could achieve out-sized proportions in air that contained about 14% more oxygen than today. The ancient supercontinent Pangaea was the lay of the land, and massive swamps pumped high levels of oxygen into the atmosphere. The ancestors of modern dragonflies go back a long way - 300 million years in fact, which is an amazing 100 million years before the first dinosaurs trundled the terrain. In fact, the dinosaurs were the new kids on the block compared to dragonflies. Unparalleled masters of flight and fen, they have thrived for millions of years. Well, maybe “enjoy” is a stretch for some of these, but one that falls into that category more often than not are the dragonflies. Crocodiles, bees, snakes, cockroaches, duck-billed platypuses, etc. There are a handful of creatures that rubbed shoulders with dinosaurs that we can still enjoy today. Some species can tolerate poor water quality and low oxygen levels and at least one Australian species doesn't even develop under water, although it still needs a moist habitat.A head on view of a green and blue striped shadow darner hovering in midair. This sensitivity means that dragonflies and damselflies are important bioindicators of water quality. This is because many Odonata larvae rely on precise water temperatures, good oxygen levels and unpolluted water to survive, and some of these habitats have been degraded. Several species are endangered, such as the species that lives in peat bogs near Bowral and Robertson in the southern highlands and the hanging swamps of the Blue Mountains (both in New South Wales). Adults may occasionally be seen flying in this tandem position. Copulation involves the male grasping the female behind the head with appendages on his abdomen while she bends her abdomen underneath his thorax to recover a packet of sperm that he has placed there. The reproductive phase may involve the establishment of territories by males, which are protected against other males of the same species. At this stage the colour of the wings and body may change and the adults may disperse from their emergence point. The adult stage has a pre-reproductive period that may last up to three weeks. The adults are predators that often capture prey while flying. After progressing through up to twelve larval stages the larvae crawl out of the water.
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