Lycaenidae is the second-largest family of butterflies (behind Nymphalidae, brush-footed butterflies), with over 6,000 species worldwide. They constitute about 30% of the known butterfly species. Adult individuals often have hairy antenna-like tails complete with black and white annulated (ringed) appearance. Many species also have a spot at the base of the tail and some turn around upon landing to confuse potential predators from recognizing the true head orientation. This causes predators to approach from the true head end resulting in early visual detection. Lycaenids are diverse in their food habits and apart from phytophagy, some of them are entomophagous feeding on aphids, scale insects, and ant larvae. Some lycaenids even exploit their association with ants by inducing ants to feed them by regurgitation, a process called trophallaxis. Not all lycaenid butterflies need ants, but about 75% of species associate with ants, a relationship called myrmecophily. These associations can be mutualistic, parasitic, or predatory depending on the species. In some species, larvae are attended and protected by ants while feeding on the host plant, and the ants receive sugar-rich honeydew from them, throughout the larval life, and in some species during the pupal stage.

Gray Hairstreak has one tail on hindwing. Upperside blue-gray with large red spot near tail. Underside of spring/fall form is dark gray, summer form is paler gray. Relatively straight postmedian line is white, bordered with orange on the inside edge. Wing Span: 7/8 - 1 3/8 inches (2.2 - 3.5 cm). Life History: Males perch all afternoon on small trees and shrubs to seek receptive females. Eggs are laid singly on flowers of host plant. Young caterpillars feed on flowers and fruits; older ones may eat leaves. Chrysalids hibernate. Flight: Two flights from May-September in the north, three-four flights from February-November in the south. Caterpillar Hosts: Flowers and fruits from an almost endless variety of plants; most often from pea (Fabaceae) and mallow (Malvaceae) families including beans (Phaseolus), clovers (Trifolium), cotton (Gossypium), and mallow (Malva). Adult Food: Nectar from many flower species including dogbane, milkweed, mint, winter cress, goldenrod, tick trefoil, and white sweet clover. Habitat: Open, nonforested sites; common in disturbed, weedy areas. Range: Throughout continental United States from southern Canada south to Mexico; southward to Venezuela. Comments: The most widespread hairstreak in North America.

Santa Catalina Mountains
Prison Camp.
Location: On White Prairie Clover beside campground road.
9/6/17

Notes: In Sabino Canyon on Smartweed both immediately above dam and at base of dam. 12/26/21.

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