LIBRARY

CHAPTER XXIII
20. Order ODONATA Fabricius 1793 1
(O-don/a-ta, from the Greek boous, 08bIlTos, a tooth.)2 German,
Libellen, Wasserjungfern, Gleichfiiigler, and Ungleichfliigler.
French, Libellulides, Demoiselles.
Damselflies, Dragonflies, Devil's Darning Needles, Snakedoctors,
Mosquito Hawks.
Medium-sized to large, slender, slow or swift-fiying, predacious insects with hernimetabolous
or simple metamorphosis, biting mouth parts, mobile head, very large lateral
compound eyes and three ocelli, strong mandibles, one-segmented maxillary palpi,
two-segmented labial palpij enlarged thorax; short, spiny legs, three-segmented tarsi;
two pairs of similar long, narrow, net-veined wings which are held straight from the
sides or over the back in repose j long, slender, cylindrical or flattened abdomen, male
copulatory organs on the second and third sternites, nymphs or naiads aquatic; with
greatly developed raptoria11abium or mask; with or without exterior caudal gills.
The damselflies and dragonflies are almost as well known as are the butterflies
and moths and are among the most interesting and fascinating of all
insects. Who has not viewed with wonder and admiration the swift hawking
flight of the dragonflies and felt amazement at their skill and poise in turning,
darting, balancing, alighting, and taking off? No other animal or mechanism
can match their versatility in the air. There is a remarkable similarity between
the lines of modern airplanes and those of dragonflies, as if man had attempted
to reincarnate these insects in powered metal. The odonates are variable in
size but rather stable in form. The largest living dragonfly appears to be the
Central and South American Megaloprepus ccerulatus (Drury) which has a wing
expanse of 7 Y2 in., whereas the smallest damselflies of the Australian genera
Agriocnemis and Austrocnemis have a wing expanse of slightly less than 1 in.
The damselflies are somewhat fragile in appearance because of their very slender
bodies and rather slow, sculling flight. The colors are plain and even somber
in some of the temperate-region species while others ate beautifully striped,
spotted, and banded with bright colors and many are blue, green, yellow, red,
and other hues. Tropical and subtropical species may be arrayed in brilliant
metallic shades equalled only by those of butterflies in the same regions. Many
forms are covered with a whitish bloom that softens the brilliance of their
I These insects have also been grouped L1nder many other names of which the following ar(l
the most important: CRYPTODONTIA Latreille 1802, LIBELLULIDES Leach 1815.
LlBELLULINA Newman 1834, PARANEUROPTERA Shipley 1904.
• Referring to the conspicl1ously toothed maxillre of the mouth Parts which are more pronounc;ed
in tnia than in any other order of insects (Mickel 1934).
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