Remembering Silver Blue Butterfly: First US Insect to Go Extinct Due to Humans

Have you ever seen a silver blue butterfly flap around your terrace or balcony garden? Chances are that you might not have because this butterfly is extinct, yet it has ignited the curiosity of scientists.  

About blue butterfly 

It was more than a century ago in the Sunset District of San Francisco. A mesmerizing bluish butterfly used to happily fly across the sand dunes of this district, laying eggs on a plant called deer weed. With developmental activities taking a full swing in this area, the butterfly vanished.  

As per reports, an entomologist collected the last Xerces blue butterfly from Lobos Greek in 1941. He, later, regretted having done by saying that he killed the last butterfly of this species.

Scientists agree that the extinction of the blue butterfly in North America was a loss of biodiversity. Many scientists are of the view that Xerces was a distinct species, yet there are scientists who do not agree with this.  

If the views of the latter are true then we have hope because there might be other such blue butterflies. Several scientists are of the view that Xerces was a subspecies of the popular Glaucopsyche lygdamus, which is a beautiful silvery-blue butterfly.  

Xerces – distinct species or not?  

A paper was published in Biology Letters recently that informed about the sequencing of near-complete mitochondrial genome of 93-year-old museum specimen. It suggests that Xerces was a distinct species.  

Corrie Moreau, Director and Curator of Cornell University insect collection and also the author of the published paper said, “it goes to show how critically important it is not only to collect specimens but to safeguard them. We can’t imagine the ways they will be used 100 years from now.”

Reintroducing Xerces butterfly? 

Genomics researcher Athena Lam at the California Academy of Sciences and the team wishes to throw light on where Xerces falls on the evolutionary scale. According to the team, such genomics studies can unfold populations of surviving species that fall under the Glaucopsyche genus. These can be reintroduced at the sand dunes of San Francisco.  

The paper suggests that good candidates for investigation would pseudoxerces or australis. The former has wings that make us remember Xerces’ shiny blue hue.  

Corrie Moreau is hopeful that the new study put the spotlight on blue butterflies that, at present, come under the endangered species. This includes: 

• El Segundo blue that resides in the coastal sand dunes of South California

• Karner Blue that is common in Wisconsin, the home of wild lupines

Another hopeful thing is that the deer weed on which the now extinct Xerces blue butterfly laid eggs has been replanted in the sand dunes of Presidio. It’s like the dunes are waiting for another future blue butterfly!  

Also Read about 7 Dazzling Blue Butterflies You Must See Atleast Once

(References:  Biology Letters from The Royal Society publishing and Indian Express)