The Square-spotted Blue is a tiny western blue butterfly that is highly specific to buckwheat species, with different populations tied to different buckwheat species across the West. Its flight period is tightly synchronized with buckwheat bloom. Males are brilliant blue above; females are largely brown. The square-shaped submarginal spots on the underside are diagnostic.
Best time to see a Square-spotted Blue
The best time to see a Square-spotted Blue is May–June, when about 72% of U.S. sightings happen, based on 3,023 research-grade iNaturalist observations.
Not certain it is a Square-spotted Blue? What bug is this? walks through what to check first and the lookalikes that catch people out.
Recent Square-spotted Blue sightings near you
Live, research-grade observations from iNaturalist. Allow location to center the map on you.
Spotted a Square-spotted Blue?
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