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#28: Odonata


© Günther Matula

Litinsects #28: Odonata

Dragonflies and damselflies (both not actually flies) make up the order ODONATA, meaning “toothed ones”, which refers to the insects’ strong and sharp mouthparts. This is one of the most primitive orders of winged insects!

Odonates are further categorized into two infraorders, the dragonflies and the damselflies. Dragonflies belong to ANISOPTERA, from the Greek anisos for “unequal” and pteron for “wing” because their front wings are slightly narrower than their hindwings (just check out the first picture). Damselflies belong to the infraorder ZYGOPTERA, from the Greek zugos meaning “even” because both wing pairs have the same shape

  • Damselflies are generally daintier looking, while dragonflies appear more robust. An easy way to differentiate between the groups is how they hold their wings at rest: dragonflies hold them open and out to the side while damselflies hold them closed and upright over their backs (see the second picture). A further, more subtle difference is that dragonflies’ eyes usually touch at the front of their heads and damselflies have a gap between their eyes
  • This group is composed of highly specialized flyers. Dragonflies have amazing maneuverability and can catch their insect prey directly out of the air. They use their legs to catch prey and to land but they cannot walk
  • Unlike other flying insects, members of Odonata can move each of their wing pairs independently. They can fly extremely fast, can hover, fly sideways, and backwards. The wings are made up of a complex network of veins with transparent membranes in between
  • Odonates start their lives as aquatic nymphs, also called NAIADS. For this reason, adults are often found near bodies of water
  • Because they rely on fresh water for their life cycle, many species are BIOINDICATORS of water quality
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