Thanks to teacher Melinda Terry and her fourth-grade Wheeling Elementary class in Aurora, the hairstreak butterfly our named as our state insect in 1996. The Colorado hairstreak captivates the eye with its dominant vivacious purple coloration that turns into wide black-to-brown bordered wings with orange spots near the bottom of the wing. Males often have larger orange spots on their wings compared to females. Another identifiable feature of the Colorado hairstreak are the “tails” on the bottom of their hind wings. Tails aid in the butterfly’s poise and grace when flying through the air.
The Colorado hairstreak (Hypaurotis crysalus) is in the Lycaenidae family, making up the second-largest butterfly family, although they only represent about 30 percent of known butterfly species. The Lycaenidae family are true butterflies, meaning they are not a skipper (darting butterfly) or a moth. Considering this, scientists are still debating how to explain the apparent differences between butterflies and moths.
The hairstreak can typically be found in oak, lightly dense, scrubby areas marked by woodlands that include their host plant, the Gambel oak, a member of the beech family. The Gambel oak provides shelter, protection and food for the Colorado hairstreak.
Art of Survival
Here in the oak trees, adults rest. Males look for female partners and once mating is successful, the female lays a single egg on the oak twigs in late summer or early fall. Eggs then hibernate over the winter to emerge as caterpillars in early spring. The young caterpillars feed on the Gambel oak leaves as they continue to develop. Little is known about their larval stage. Food is also found in the groves, where Colorado hairstreaks feed on tree sap, mud and raindrops solely. Tree sap is denatured by raindrops in order for hairstreak butterflies to digest the viscous liquid. The Colorado hairstreak will sometimes also feed on honeydew left by aphids — a sugary, liquid waste. Although most butterflies feed on flower pollen through their proboscis, the Colorado hairstreak possesses a “food-straw,” resembling a long tongue, much too short for feeding on most flowers.
The hairstreak is a native butterfly of Colorado that is prevalent in many areas of the Southwestern United States from Utah to New Mexico and into Mexico. Best chance of seeing the Colorado hairstreak will be in their oak habitat, as they rarely leave these small groves. Males are also often found in groups on a patch of mud or moist sand. This is called “mud-puddling,” and the complete nature of this grouping is not known, but it is thought that Colorado Hairstreaks and other butterflies that act similarly draw water from the mud that contains dissolved minerals needed by the Colorado hairstreak.
From Low To High
The Colorado hairstreak makes one flight from June to August from low to high altitudes. One generation is born per year, adults being found from June through August. Females live for nine days on average and males live for only five days on average.
Fine specimens are on display at the University of Colorado’s Museum of Natural History in the Entomology Section for the public’s viewing pleasure, and, of course, you could always venture out into a grove of Gambel oak to seek out this elite member of the butterfly world.
Celeste Drago is a naturalist at Walking Mountains Science Center in Avon.
The Colorado hairstreak will sometimes also feed on honeydew left by aphids — a sugary, liquid waste. Although most butterflies feed on flower pollen through their proboscis, the Colorado hairstreak possesses a “food-straw,” resembling a long tongue, much too short for feeding on most flowers.