|[Note Guidelines] Photographer's Note|
|I was studying for my first state examination in medecine, when I was amused by the dragonfly turning around me and my books in our garden. I still remember each position of the dragonfly in the garden - but I do not have an idea about the theme I studied that day...|
Anyway, I saved this great moment in my memory and passed the exam...
Odonata is an order of insects, encompassing dragonflies (Anisoptera) and damselflies (Zygoptera).
These insects characteristically have large rounded heads covered mostly by well-developed, faceted eyes, legs that facilitate catching prey (other insects) in flight, two pairs of long, transparent wings that move independently, and elongated abdomens. In most families there is a structure on the leading edge near the tip of the wing called the pterostigma, which actually is a thickened, blood–filled and often colorful area called a cell. Cell in this case means a closed area of an insect wing bounded by veins. The functions of the pterostigma are not fully known, but it most probably has an aerodynamic effect and also a visual function. More mass at the end of the wing may also reduce the energy needed to move the wings up and down. The right combination of wing stiffness and wing mass could reduce the energy consumption of flying. A pterostigma is also found among other insects, like bees. Although generally fairly similar, dragonflies differ from damselflies in several, easily recognizable traits. Dragonflies are strong fliers with fairly robust bodies and at rest hold their wings either out to the side or out and downward (or even somewhat forward). Damselflies tend to be less robust, even rather weak appearing in flight, and when at rest most species hold their wings folded back over the abdomen (see photograph below, left). Dragonfly eyes occupy much of the animal's head, touching (or nearly touching) each other across the face. In damselflies, there is typically a gap between the eyes.
Odonates are aquatic or semi-aquatic as juveniles. Thus, adults are most often seen near bodies of water and are frequently described as aquatic insects. However, many species range far from water, seeking open fields and hilltops where they prey on smaller insects, catching these in flight. Dragonflies in particular are the raptors of the insect world and absolute masters of maneuverings in flight.
Picture was scanned with my old scanner and I reduced noise afterwards.
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