| Dragonflies and damselflies of Singapore |  |
Introduction
Dragonflies and damselflies are insects belonging to the order Odonata. There are over 100 species of dragonflies and damselflies in Singapore. The rarer ones are usually those which live deep in our forests. The species list in this website is not exhaustive of course, due to my limited knowledge.
English common names
Many of the English common names used in this website have already been proposed in unpublished writings. We do stress that these names are essentially ‘nicknames’, to be used mainly within the local community. We urge anyone developing a serious interest in dragonflies in Singapore to learn and use the scientific names. It is worth of the trouble.
A Brief Overview of Odonata (Dragonflies and damselflies)
The name Odonata, derived from the Greek "odonto-" meaning tooth, refers to the strong teeth found on the mandibles of most adults.
Dragonflies are a well known and fascinating order of insects. They are more common in warmer parts of the world than in temperate areas. They are conveniently divided up into two groups Anisoptera the true Dragonflies which rest with their wings out from their body and Zygopteran or Damselflies who hold their wings above their body. There are exceptions.
Dragonflies have strongly biting mouthparts and are active and aggressive carnivores, preying mostly on other insects. They catch insects on the wing. The adults have massively large eyes. These eyes may each contain as many as 30 000 individual lenses or ommatidia. Because of this Dragonflies have exceptionally good eyesight and have been known to respond to stimuli from more than 40 feet away. They have very small and poorly developed antennae though.
They have two pairs of almost equally sized long thin membranous wings. Unlike most insects, which either flap both pairs of wings in unison (i.e. Bees and Butterflies), or only flap the hind pair (i.e. Beetles), or only have one pair (i.e. Flies), Dragonflies can flap or beat their wings independently. This means the front wings can be going down while the back ones are coming up. Dragonflies are excellent fliers, hover and fly backwards quite easily.
Dragonflies are a very ancient order of insects and fossils exist from more than 300 million years ago. Dragonflies are also relatively large insects, even now, but in they past they were much larger. The largest Dragonfly in the world now is actually a Damselfly (Zygoptera) Megaloprepus caerulata from Costa Rica with a wingspan of 19.1 cm and a body length of 12 cm. Tetracanthagyna plagiata from Borneo is the largest Anisopteran or true Dragonfly. The smallest is probably Agriocnemis nana (occuring throughout Peninsular Malaysia, Thailand, Burma and southern Vietnam) with a wingspan of just 1.8 cm.
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