![]() ![]() ![]() Flies), Dragonflies can flap or beat their wings independently. Bees and Butterflies), or only flap the hind pair (i.e. Unlike most insects, which either flap both pairs of wings in unison (i.e. Both pairs of wings usually have a stigma (a dark or coloured patch near the middle of the leading edge) and a mass of cross veins, giving them the appearance of being a mesh. ![]() They have two pairs of almost equally sized, long thin membranous wings. They have very small and poorly developed antennae though. Because of this, Dragonflies have exceptionally good eyesight and have been known to respond to stimuli from more than 40 feet away. These eyes may each contain as many as 30,000 individual lenses or ommatidia (your eyes have only one lens each). The adults have massively large eyes, often meeting at the top of the head in Anisopterans.Įxtreme macro shot of dragonfly eye on yellow leave Odonata is one of the most popular orders of insects, as evidenced by the many long established organisations such as Odontalogica, Dragonfly Society Of America and British Dragonfly Society.ĭragonflies have strongly biting mouthparts and are active and aggressive carnivores, both as adults and as young (called nymphs), preying mostly on other insects. In this article when I say ‘Dragonflies’ I will mean both Anisoptera and Zygoptera, but I will use these terms separately when talking about the individual groups. The Order Odonata is conveniently divided up into two groups: Anisoptera, the true Dragonflies which rest with their wings out from their body in a cross shape and Zygopteran or Damselflies, who hold their wings above their body. Of the 5,300 named species world-wide, only 38 live and breed in Britain. They are more common in warmer parts of the world than in temperate areas like the UK. You will likely see plenty of them as you go out into the field in late summer, normally near water. They are more than curiosities macros are intermediaries in the story of a larger ecology where they recycle nutrients and subsequently feed the wildlife that we humans are more likely to notice.Odonata (Dragonflies) are a well known and fascinating order of insects. They carry forest floor resources with them throughout the forest and adjacent waters. Macros are key players in the enrichment of a wet forest. As these organisms are eaten by predators and then, even larger predators the nutrients and energy of the cast‐offs from previous years become the building blocks of a fresh new spring. ![]() There are shredders, nibblers, and scrapers with unique appendages and mouth parts that collectively transform dead material into living tissue. Then, the macros come along in many sizes and shapes with an array of skills and appetites. Microscopic algae, fungi and bacteria often initiate the process. To digest these coarse resources a variety of organisms are engaged. It is often said that vernal pools are fueled by detritus, fallen leaves, limbs and other plant materials that fall to the forest floor. Predaceous Diving Beetle Larva, photo by Judy Semroc Many insects, including dragonflies, damselflies, beetles, bugs and flies use this strategy. Other macros only use vernal pools to lay eggs and feed as they grow, but later leave the pool as adults before the waters dry down. Fairy shrimp, that only live in vernal pools, are the premiere example of this strategy. One life‐cycle strategy is to hatch very early, mature, breed and lay eggs that will become dormant until the next season. Many of them become active in winter, even below a layer of ice. Macroinvertebrates are especially suited to life in temporary waters. Others range in size down to the tiniest speck. The largest macros of vernal pools are crayfish and dragonflies that, as adults can grow to more than three inches in length. Those that can be seen without magnification are collectively known as macro‐invertebrates (macros). Vernal pools are populated by dozens, if not hundreds, of small organisms that are not vertebrates, so called because they do not have backbones like frogs and salamanders. ![]()
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