Widow Skimmer

Widow Skimmer
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Scientific Classification

Kingdom- Animalia
Phylum- Arthropoda
Class- Insecta
Order- Odonata
Family- Libellulidae
Genus- Libellula
Species- Libellula Luctuosa
Morphology

Widow Skimmer females and males have both similarities and differences, regarding their physical appearance. Both sexes have blackish-brown areas up to halfway to the tip and the tips of the wings are smoky-white, though there are some differences in the rest of the coloring. The body and wings become increasingly dusted with a whitish color as the Widow Skimmer ages. As opposed to having a hard exoskeleton, the body is somewhat fleshy, and the thorax is sometimes a bit hairy. The wingspan of a Widow Skimmer is usually approximately 1 1/8 to 3 1/2 inches, which would equate to 30 to 90 millimeters. The Widow Skimmer body is medium sized, usually around 1 5/8 to 2 inches, which is equivalent to 42 to 50 millimeters.
Nymphs
The larvae of the Widow Skimmer are colored in a very colorless light brown that makes them look similar to the leaves and sediment in the water in which they reside. This helps to camouflage them from predators and as they wait for possible prey. The Water Skimmer nymphs possess rather large eyes that help them to spot both prey and predators.
Mature Males
Widow Skimmer males have dark brown bands on all wings bordered by a distinctive outer band of white. Their eyes are dark brown and black. The males Widow Skimmer’s abdomens tend to be a steely blue color with dark areas that go to the base of the wings. The abdomen will become increasingly dusty-white as the dragonfly ages.
Immature Males and Females
Female and immature male Widow Skimmers are quite different from the mature males. They do not have the white marks on their wings, however they do have the brown bands on each wing like the mature males do. The females and young males have a brown thorax in which there is a dorsal stripe of yellow and a brown abdomen edged with yellow stripes. The female Widow Skimmer's physical appearance is the main reason for the first half of the species' common name, comparing the brown-black patches on the their wings to a widow's black veil. In fact, their scientific name luctuosa means sorrowful and mournful.
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Male Widow Skimmer
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Female/Immature Male Widow Skimme
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The eyes of a Widow Skimmer nymph
Habitat Needs

Widow Skimmers are most commonly found at ponds, lakes, and marshes, and are also found sometimes at slow-moving water sources like streams and creeks. Some Widow Skimmers will wander far away from water to hunt. While also requiring a water source in their habitat, they may wander to a meadow or field to find additional food sources, which would be smaller flying insects. Widow Skimmers defend an area of approximately 250 square yards and defend their favored perch. Widow Skimmer larvae live in still water, but mature Widow Skimmers tend to stay near slow-moving or still water and sometimes range over open land.
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An example of a possible habitat
of many Widow Skimmers.

Geographic Range

Widow Skimmers are very commonly found all across the United States. However, they are not found normally in the higher areas of the Rocky Mountains in Canada and the United States, in southern Quebec and southern Ontario regions in Canada, or the Great Basin region of the United States. The Widow Skimmer is often found in similar regions to that of the Eastern Pondhawk, also know as the Green Clearwing. They will most likely be found in areas from Ontario and the Atlantic Coast to Georgia and the Gulf Coast, areas west from Texas, northern Mexico, and south of South Dakota. They may also be found in parts of northern Mexico and southern Canada. Although Widow Skimmers are distributed across the United States, they only reached northern California in 1990. This species spread north farther than formerly due to habitat alterations from men. Widow Skimmers are found in large numbers across this very large region from Spring through Autumn.
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Map of the Libellula luctuosa's geographic location
Mating Behavior

Widow Skimmer females and males are seen at ponds and lakes when mating. The male will grasp the female at the back of the head near the eyes after flying in tandem for a period of time. The male will release the female after mating so that the female can hover over the surface of a water source such as a pond, lake, or marsh and dip her abdomen under the water to deposit her eggs. Usually in other dragonfly species, the male stays near the female even after she lays her eggs, however, the Widow Skimmer male will leave the female right after the eggs are deposited. This is one of the reason for the "widow" part of this dragonfly species' common name.
Life Cycle

Widow Skimmers start as eggs, laid in pond or lake water on the bottom sediment or an aquatic plant by a female who is often unattended by the male. The Widow Skimmer nymphs spend their lives in that state feeding on aquatic insects, sometimes in vernal pools, in which they are among the top predators, and molting and growing to prepare to leave the water. Some nymphs may be able to survive desiccation, or waterlessness, and the freezing of water by locating themselves in sheltered, moist areas logs and rocks or by burrowing underground. The naiads, juvenile insects, will crawl up to a few feet from water and cling to vegetation. In April in the South, and late summer in the North, they will emerge as adults. Once they shed their skin one final time, the newly emerged adult Widow Skimmer will remain helpless while it pumps sufficient fluids into its wings. When there is adequate fluids in the wings, the Widow Skimmer will flex its wings to reinforce them, then take flight for the first time. For the rest of their adult life, they will feed on small flying insects, mate, and aggressively defend their territory.
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The larval stage of the Widow Skimmer
The immature state of the male Widow Skimmer/
the mature state of the female.
The mature state of the male Widow Skimmer.
Feeding Habits

Naiad Widow Skimmers feed on small aquatic insects, other invertebrates, as well as amphibian larvae. When they mature further, the Widow Skimmer dragonfly will feed on small flying insects, such as mosquitoes, biting flies, and midges, which they may consume thousands of. Both the female and the male Widow Skimmers will perch on vegetation in open areas, like meadows and fields. They will claim and ferociously defend their favorite perch from other Widow Skimmers looking for a perch. The Widow Skimmer will wait until their prey in sight to start their attack. Once the prey is in sight, the Widow Skimmer will swoop in and capture their quarry. They will proceed to eat the small flying insect with their small, scissor-like mouth-parts.
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These are three of the small flying insects that Widow Skimmers will consume.
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A closer picture of the Widow
Skimmer's mouth-parts.

A female Widow Skimmer, feeding on a moth.
http://www.youtube.com/watch?v=RQLBXuNKJRI
Ecological Role

The Widow Skimmer has few, although important, ecological roles. Widow Skimmers do nothing extremely helpful to the environment around them, however they do assist in the population of many small flying and aquatic insects. Since adult widow skimmers feed on small flying insects and juvenile Widow Skimmers feed on aquatic insects, they help to keep the populations of those insects under control. For example, the Widow Skimmer maintains the population of insects like mosquitoes, biting flies, and midges. These insects could have very negative effect were its population to spike out of control, such as the spreading of the infectious disease, Dengue fever.
Videos


A description of the male Widow Skimmer
http://www.youtube.com/watch?v=nH7POjVSDk8
(View from 7:38 to 8:23)
A male Widow Skimmer dragonfly.
http://www.youtube.com/watch?v=cNN9EeeWkuA
Glog

Visit our glog on Glogster.com at http://dmundhenk.glogster.com/Widow-Skimmers/ !

Sources

http://creagrus.home.montereybay.com/WidowSkimmer.html
http://www.stephencresswell.com/d/luctuosa.html
http://www.njodes.com/Speciesaccts/skimmers/skim-wido.asp
http://bfec.kenyon.edu/dragonfly/widowskim.htm
http://www.loudounwildlife.org/HHWidowSkimmer.htm
http://greennature.com/gallery/libellulidae/widow-skimmer.html
http://creagrus.home.montereybay.com/WidowSkimmer.html
http://dearmond.net/node/12
http://www.insectsofwestvirginia.net/d/libellula-luctuosa.html
http://mobugs.blogspot.com/2009/10/widow-skimmer.html
http://ecobirder.blogspot.com/2008/10/widow-skimmers-at-fort-snelling.html