Hairstreaks belong to the large worldwide family Lycaenidae, which also includes all blues, coppers and metalmarks.

Hairstreaks are small butterflies, often with taillike extensions or “hairstreaks” on their hindwings, particularly in members of the genus Satyrium. In Washington State there are eighteen species of hairstreaks, six of them in the genus Satyrium. Butterflies in the genus Satyrium fly in mid summer, peaking in July, and are highly valued by butterfly enthusiasts.

The pretty Coral Hairstreak is probably the most sought after species in the genus Satyrium. While its reported flight period in Washington extends from early June to mid August the Coral Hairstreak is usually quite scarce, seldom common even locally, and can be quite difficult to find at all. This species does habituate the same preferred habitats year after year however, and can reliably be found by visiting places where it has been seen on previous years.

Satyrium titus is a fairly widespread North American species, occurring across Canada from British Columbia to the Atlantic, and south through much of the United States except the southernmost parts. Within Washington State titus is entirely restricted to the east side, occurring mostly in a belt along the eastern foothills of the Cascades. Outlier populations have been found spotted here and there especially in low mountainous or hilly areas elsewhere in eastern Washington.

Starkly white eggs of a typical “compressed sphere” Lycaenid shape are oviposited in mid to late July, singly or in small clusters, in small crevices and protected areas on the woody parts of host plants. The preferred plant eaten by S.titus larvae is usually chokecherry (Prunus virginiana) but sometimes also wild Rose (Rosa woodsii).  Western Serviceberry (Amelanchier ainifolia) has also been reported. Satyrium titus overwinters in the egg stage, and does not hatch the following spring until the larval host plant has begun growing its delicate new leaves. The larvae feed only on leaves, developing moderately slowly but ultimately reaching a surprisingly large size of about 21 mm. In the later instars the larvae become uniquely and dramatically colored, bright green in the middle and wine-red on both ends. The cycle from newly hatched egg to mature final instar is completed in about 24 days (in captivity), whereupon the larva pupates to a camouflaged spotted brown chrysalis, typically hidden under debris at the base of the plant. On eclosing the adult butterflies mate and start the cycle anew.

Adult Coral Hairstreaks are as unmistakable as their unusual larvae. Along the entire outer margin of the ventral hindwing (VHW) a row of large bright orange spots is set against a contrasting dark gray (fresh) or brown (worn) ground color. No other Washington butterfly has such a dramatic orange spot row in combination with the “tails” characteristic of the genus Satyrium (but compare also California Hairstreak). There may also be a trace of small orange spots along the ventral forewing, although these are easily overlooked. Paralleling the orange spots on the proximal (body) side of the VHW is a corresponding row of black spots ringed with white halos.

Adults nectar readily, particularly on Showy Milkweed when available. While distracted for nectar they are sometimes easily approached for closeup photography.   Adults  are often found in the higher elevation fringes of the sage-steppe, adjacent to the lower timber line, areas where typically chokecherry and milkweed occur together, but they also occur in hotter, drier parts of the Columbia Basin. Watch for the colorful Coral Hairstreak on sunny days in July, especially along watercourses and roadsides where its food and nectar plants occur.

All Photos by Dave Nunnallee

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