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Quick
Facts
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Common Name:
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Damselflies
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Other Common Names:
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Bog dancers, damsels, devil’s darning
needles & narrow wings
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Genus / Species: |
Varies. Several genera occur in the
Galveston-Houston region
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Type
of Beneficial:
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Insect predator
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Type of Metamorphosis:
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Immature stages appear different from adults (i.e., complete metamorphosis)
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Beneficial Stage(s):
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Immature stages and adult stage are insect predators
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Prey:
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Immature stages are aquatic and prey on freshwater organisms including
mosquito larvae and other small aquatic insects. Adults prey on flies,
mosquitoes and moths; some species prey on beetles and caterpillars.
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Distribution:
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Occur across the Galveston-Houston region
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Mounted
Specimen?
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Yes
(mounted specimen for viewing available in insect collection at County Extension
Office)
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The order Odonata is comprised of two suborders–the Zygoptera or damselflies and
the Anisoptera or dragonflies. Odonata means "toothed,” referring to the chewing
mandibles of these beneficial insects.
Dragonflies and damselflies, like cockroaches, are two of the oldest insect
groups. During prehistoric times, they were as big as hawks. You can find
Odonate fossils from Kansas to Siberia. These fascinating creatures had
wingspans of almost 30 inches and were the largest insects to ever live.
Currently, there are estimated to be more than 4,700 species of Odonata
worldwide and Zygoptera accounts for one-third of them. Zygoptera is native to
all regions of the world, except Antarctica.
The term “Zygoptera” means "paired wings." Damselflies are also commonly known
as bog dancers, damsels, devil’s darning needles and narrow wings. There
are four families of damselflies. Calyopterygidae are black winged (some have
half black wings) with a red spot at the base. The Coeangrionidae
have many body colors but always have clear wings. Lestidae, also known as ‘Spreadwings’,
are unlike other damselflies because they perch vertically with their wings open
when at rest (similar to a dragonfly). Lestidae usually have a yellow, bronze or
metallic green sheen to them. The Protoneuridae are small thread-tailed
damselflies inhabiting streams in far south Texas. Interestingly, the largest
species in Texas is Archilestes grandis in the family Lestidae. The smallest
known damselfly is the Southeast Asian species, Agriocnemis femina.
Damselflies are delicate, weak-flying insects. An adult damselfly has a long
slender body, which is green, blue, red, yellow, black, or brown and often
brightly colored. The color of some species will change with a variety of
environments, fading from bright blue to dull purple responding to cool
temperatures or light.
Males of most damselfly species are brighter-colored than females. Both genders
have broad, oblong heads with large, widely separated bulging eyes and very
short antennae. When resting, damselflies hold its two pairs of four magnificent
membranous wings vertically rather than horizontally. Damselfly adults use their
hairy covered hind legs to capture prey as they fly. Once caught, they will hold
the prey in their legs and devour it by chewing.
Adults are usually seen during the daytime throughout the year. Damselflies are
carnivorous insects that live and breed near freshwater habitats. They commonly
fly in tandem during mating, as the damselfly's mating pattern is quite unusual.
There are three stages in the damselfly life cycle: egg, naiad (the nymph of a
damselfly) and adult. Eggs are either laid in water, on underwater vegetation,
or other water-filled cavities such as in bromeliads. Eggs usually hatch within
1-to-3 weeks. Once hatched, the naiad has an elongated body, long legs
and three leaf-like appendages or gills on its tail.
Damselflies live for 2 months to 3 years as nymphs, undergoing five to
15 molts as they grow. At this stage, naiads like the adults, are fierce
predators. They prey on freshwater organisms, mosquito larvae, various small
aquatic insects and other arthropods within their reach. At the last stage, a
naiad crawls out of the water and clings to a plant, drying its skin.
After a few minutes sunbathing, the outer skin splits open at the head and the
adult damselfly struggles, pulling itself out of its old skin. Its new legs
harden, holding onto the plant, its wings slowly expand and then the damselfly
flies away from the water. At this time, it is extraordinarily hungry,
ravenously eating flies, mosquitoes and other small insects. Once the adult is
sexually mature, it returns to an area near water to breed.
The life span of damselflies varies by species. The amount of time that the
nymphs spend in the aquatic stage depends on temperature, light and food
availability. As an adult, they may survive for a few weeks or for several
months. In general though, tropical species spend less time in the aquatic stage
and more time in the adult stage than temperate species.
Damselflies are extremely beautiful, beneficial predators because they help
control populations of harmful insects. Adults consume large quantities of other
insects such as flies, mosquitoes and moths and some eat beetles and
caterpillars.
One way to conserve them is by avoiding indiscriminate use of pesticides.
Damselflies are also a very important group of insects in stream and pond
ecosystems. They are often used as an indicator of whether water is clean or
polluted. The quality of the environment can be monitored by damselflies as
their presence is strongly affected by different factors such as water flow,
pollution and vegetation.
The destruction and alteration of freshwater habitats are the greatest threats
to damselfly species worldwide. Without clean water damselflies are unable to
breed. An alteration of habitats through global warming may also pose a threat
to damselfly populations in the future.
Lastly, contrary to popular belief, adult damselflies do not bite or sting.
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