Alternate Common Name: Blue Mistletoe Hairstreak.
Note: This species includes a subspecies, millerorum, which occurs in Mexico.
This species ranges from southern British Columbia and Alberta south to southern California and into Mexico. In the U.S., it extends as far east as Colorado and New Mexico. It occurs through much of Idaho, but predominantly in the central portion of the state.
Typical habitat includes coniferous and mixed forests and desert canyons.
Caterpillars feed on the external parts of dwarf mistletoes (Arceuthobium
spp.), a parasitic plant that lives on a variety of conifers.
Adult: Butterflies drink flower nectar, often from flowers belonging to the sunflower family (Asteraceae).
There is one generation of caterpillars through most of its range while there may be several in the south. Each undergoes five stages of growth, called instars. The caterpillar is equipped with a honey gland, also known as a dorsal nectary organ, which emits a sugary solution agreeable to ants. The ants feed on the solution and in turn protect the caterpillar from predators. Pupae overwinter in a physiological state called diapause in the mass of plant growth of the host tree, caused by the mistletoes presence. Adults generaly fly from March through October, with most adults in the northern part of its range appearing in June. The thin "tail" on each of the hindwings of adults is thought to mimic insect antennae and thus misleads bird predators into biting at the wrong end and only getting a mouthful of wing, while the butterfly escapes in the other direction.
Males perch to wait for receptive females. Females lay eggs singly on mistletoes.
|Idaho Status:||Unprotected nongame species.|
|Global Rank:||G5; populations are widespread, abundant, and secure.|
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