Spring Azure (Celastrina ladon)
Spring Azure (Celastrina ladon)
Nelson Lake Marsh, Kane County, Illinois 
April 17, 2005

Many experts think that the Spring Azure is a complex of similar species with Spring Azure and Summer Azure being two of them.  However, I have counted them as one species in the Fermilab total. 

In any case, this would be a Spring Azure, being out so early in the season.  Spring Azures are among the first butterflies to emerge in the spring. 

Spring/Summer Azure (Celastrina ladon/neglecta)
Fermilab, ELM-19 woods edge 
DuPage County, Illinois 
June 1, 2004 

This is may actually be a Summer Azure (Celastrina neglecta).  Note also the much lighter appearance than the Spring Azure above, which is not diagnostic of the Summer Azure, but according to field guides is a fairly typical difference. 

Spring/Summer Azure (Celastrina ladon/neglecta)
Nelson Lake Marsh, Kane County, Illinois 
July 9, 2005 

This is most likely a Summer Azure (Celastrina neglecta), being a fresh individual in July. 

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