The genera Callophrys (green hairstreaks),
Incisalia (elfins) and Mitoura (brown hairstreaks) have been the
subject of intense taxonomic study in recent years, with frequent changes in
scientific and English names. While the three genera seem to be fairly distinct
here, when world species are taken into account the distinctions between them
appear more blurred. That is probably why some authors prefer to regard them
as distinct genera, while others prefer to lump them all under Callophrys.
There has also been variation in the spelling of augustinus or augustus,
so that variations from Incisalia augustus to Callophrys augustinus
are to be found in the literature. Regardless of the current scientific name,
the English name has usually been given as Brown Elfin (I have also seen Salal
Butterfly). C. Guppy, however, has recently proposed that the species on the
coast, including Vancouver Island, is a distinct species, which he names the
Western Elfin Incisalia iroides. Whatever one cares to call it, the individual
illustrated is from southern Vancouver Island.
In this area, the usual foodplant is Gaultheria shallon, but I have also found it on the related Arctostaphylos uvaursi and Arbutus menziesii, as well as on the quite unrelated Holodiscus discolor. The caterpillar is usually an unmarked bright green; the second example shown, with striking yellowish and reddish markings, was on a quite unusual foodplant – Ceanothus thyrsiflorus. Like many lycaenids, the caterpillars prefer the flowers to the leaves. The species is single-brooded. The pupa overwinters, and the butterfly appears early in the spring.