www.small-beings.org
www.small-beings.org
Kleinlibellen oder Wasserjungfern (Zygoptera) sind eine Unterordnung der Libellen (Odonata), die in 19 Familien mit rund 2600 Arten untergliedert werden. Aus Deutschland sind 28 Arten der Kleinlibellen bekannt.
Die Zygoptera, auch bekannt als Kleinlibellen, sind in Europa hauptsächlich mit einer Flügelspannweite von bis zu 70 mm vertreten, wobei die kleinste Art nur 19 mm misst. Ihr Körper ist schlank und ihre Augen sind seitlich am Kopf angeordnet. Die Flügel werden in Ruhestellung nach hinten über den Hinterleib gelegt, ohne ein Flügelgelenk zu verwenden. Der Flug der Kleinlibellen ist im Vergleich zu größeren Libellenarten langsam und flatternd. Die Larven leben im Wasser und haben am Hinterleibsende blattförmige Anhänge, die zur Atmung und Fortbewegung dienen. Sowohl die Imagines als auch die Larven ernähren sich von Beute. Alle Libellenarten sind in Deutschland durch die Bundesartenschutzverordnung geschützt, und es ist noch nicht endgültig entschieden, ob die Larvalhäute gesammelt werden dürfen oder ob eine Ausnahmegenehmigung erforderlich ist. Quelle: Wildermuth, H., Gonseth, Y., Maibach, A. (2005). Odonata. Die Libellen der Schweiz. Fauna Helvetica, Band 12.
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies (which constitute the other odonatan suborder, Anisoptera) but are smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Jurassic, and are found on every continent except Antarctica. All damselflies are predatory insects; both nymphs and adults actively hunt and eat other insects. The nymphs are aquatic, with different species living in a variety of freshwater habitats including acidic bogs, ponds, lakes and rivers. The nymphs moult repeatedly, at the last moult climbing out of the water to undergo metamorphosis. The skin splits down the back, they emerge and inflate their wings and abdomen to gain their adult form. Their presence on a body of water indicates that it is relatively unpolluted, but their dependence on freshwater makes them vulnerable to damage to their wetland habitats. Some species of damselfly have elaborate courtship behaviours. Many species are sexually dimorphic, the males often being more brightly coloured than the females. Like dragonflies, they reproduce using indirect insemination and delayed fertilisation. A mating pair form a shape known as a “heart” or “wheel”, the male clasping the female at the back of the head, the female curling her abdomen down to pick up sperm from secondary genitalia at the base of the male’s abdomen. The pair often remain together with the male still clasping the female while she lays eggs within the tissue of plants in or near water using a robust ovipositor. Artificial fishing flies that mimic damselfly nymphs are used in wet-fly fishing. Damselflies are sometimes represented in personal jewellery such as brooches.
The Zygoptera, or damselflies, are an ancient group, dating back to the Late Jurassic. Molecular analysis in 2021 has revealed that most of the traditional families within this group are monophyletic, but some will need to be reorganized. Currently, there are 27 damselfly families, with more likely to be created in the future. Damselflies have similar body plans to dragonflies but have smaller, widely separated eyes. They are sexually dimorphic, with males often being brightly colored. Damselflies are found on all continents except Antarctica and are mostly found in freshwater habitats. They feed on flies, mosquitoes, and other small insects. Conservation efforts for damselflies should focus on protecting their habitats from deforestation, water pollution, and other human disturbances.