Species Insects & ArthropodsCeraunus Blue

Ceraunus Blue

Hemiargus ceraunus

CommonInsect & Arthropod
Illustration of Ceraunus Blue (Hemiargus ceraunus)

The Ceraunus Blue is a tiny blue butterfly of the deep South and Southwest, with males showing violet-blue above and females being largely brown. Its underside pattern of spots and a partial second eyespot near the tail base is distinctive. It is a rapid flier that produces multiple generations in warm climates. Its small size makes it easy to overlook.

Habitat
Dry scrub, roadsides, and open areas of the South
Diet
Larvae: flowers and seeds of hairy indigo and other legumes. Adults: nectar
How common
Common

Best time to see a Ceraunus Blue

The best time to see a Ceraunus Blue is July–November, when about 64% of U.S. sightings happen, based on 19,189 research-grade iNaturalist observations.

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Not certain it is a Ceraunus Blue? What bug is this? walks through what to check first and the lookalikes that catch people out.

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