Reakirt's Blue
Hemiargus isola
(Echinargus isola)
Among the many butterflies and other insects visiting flowers of Desert Broom (Baccharis sarothroides) at Bumblebee, Yavapai Co., Arizona, USA. 23 October 2012.
Several small blue butterfly species can be found in the Sonoran Desert; this
is one of the less common. The row of dark black spots on the underside of the
forewing makes it easily recognized. They frequent flowers and when perched
often hold the wings folded over the dorsum, thus showing the distinctive
spots. Wing span is about 12 mm. The caterpillars are small, slug-like and
well camouflaged on foliage of mesquites.