The four-spot skimmer dragonfly (Libellula quadrimaculata) was designated the official state insect of Alaska in1995.

The four-spot skimmer dragonfly won among 4 insects voted on by Alaskan schoolchildren. The runners up included the Unmarked slender mosquito, the mourning cloak butterfly, and the bumblebee.

Excerpt from Dragonfly Wins State Title; Mosquitoes Miffed by Ned Rozell:

"After an energetic campaign by students from the Auntie Mary Nicoli Elementary School in Aniak, the winner is the four-spot skimmer dragonfly. It mauled the mosquito. It battered the butterfly. And it bested the bumblebee in a tight contest to be the Last Frontier's official insect.

Dragonflies, also known in some parts as mosquito hawks, horse stingers and devil's darning needles, dart through the Alaskan air, tiny helicopters in search of mosquitoes and other prey. Actually, it's an insult to compare the flying ability of dragonflies with any man-made aircraft. Dragonflies can stop on a dime at 35 miles an hour, fly backward, and cut turns that are too abrupt for any human pilot to stomach."

Dragonflies live in many parts of North America around lakes, ponds, and slow-moving or still water. They eat mosquitos, midges and black flies. It has been jokingly said that the children voted for the dragonfly because they prey on Alaska's "unofficial state bird" (the mosquito), but state representative Irene Nicholia said it was because "The dragonfly's ability to hover and fly forward and backward reminds us of the skillful maneuvering of the bush pilots in Alaska."

Source:

Dragonfly Wins State Title; Mosquitoes Miffed: U of Alaska
Symbols of Alaska: Fairbanks Alaska Visitor Information

Links:

Dragonflies and Damselflies: Odonata Information Network
State Insects - 50 States List