Alaska State Insect
Four-spot skimmer dragonfly (common name)
Libellula quadrimaculatas (scientific name)
The four-spot skimmer species is about 300 million year old. Skimmers are large insects (almost two inches, or 4.2 cm, long) and have wingspans longer than their bodies. The bodies are comprised of a head with very large eyes, a stout furry thorax, and a vivid orange abdomen with a yellow line along each side. The base of the hind wings is rounded, and there are two dark– brown spots at the leading edge of each set of wings, making the insect’s appearance quite distinctive.
Wingspan: 2 3/4–3 1/8 in (6–8 cm)
Larvae: Odontate larvae are called nymphs or naiads. They feature short abdomens covered with spines and knobs, small eyes, long antennae, short legs, and a double-hinged jaw that juts out to capture prey with hooked teeth.
Adult: Three months
Larva: The larval stage comprises the majority of the insects’ lifespan. The larva goes through a dozen molts over a period of typically two years before its metamorphosis into a flying insect.
Ponds, vernal pools, and slow-moving rivers.
Range: Labrador to New Jersey in the east; Alaska to Arizona in the west. The four-spot has a circumpolar range around the northern hemisphere from Europe to Japan as well as across the United States and Canada.
Flight period: Early April to mid-August. They are most active in June and July.
Conservation status: Secure globally, but now rare in parts of its traditional range.
Males often perch around the margins of pools and ponds with good visibility and will often return to these same perches. The male is highly aggressive and will patrol its territory and defend it from incursions by other dragonfly males. Both sexes are in almost constant motion, and mating even takes place in the air. Females lay their eggs on floating vegetation in April through October, and the eggs hatch shortly afterwards. Larvae overwinter before hatching in the spring. The four-spot is an aggressive hunter of other insects, including smaller dragonflies. They do not bite or sting, but rather bite their prey.
Adults: Small, flying insects primarily mosquitoes, gnats, and midges.
Larvae: Aquatic insect larvae, tadpoles, and even minnows.
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|Author: World Trade Press|