Eastern Tailed-blue

Here's 1 of our Eastern Tailed-blue butterflies. Though I usually identify these butterflies by a little piece of their hind wings that sticks out a bit (aka "the tail") [1], in this particular picture the background makes this a little hard to see. The other field mark that differentiates this butterfly from the Azure Complex butterflies is a small orange spot on the underside of the hind wing, which you ought to be able to see in this picture. Given that sometimes part of the wings can be torn off, the orange spot is probably a slightly more reliable field mark, though it's easier for me to remember that Eastern Tailed-blues have "tails".

Although being able to see that orange spot is good for identification purposes, the view of them with their wings up does have a downside. The primary way to identify a female from a male is if the top view of the wings is gray rather than a purplish-blue. I'm not aware of a way to tell the gender from this view; if that's important to you, I think you'd simply have to wait until it opens its wings.

May 14, 2023 at Duke Farms
Photo 292808228, (c) jpviolette, some rights reserved (CC BY-NC)

[1] This "tail" is not unlike the "tails" on swallowtail butterflies (like this Spicebush Swallowtail) except that the tails on Eastern Tailed-blues tend to be much smaller and less conspicuous. Taxonomy-wise though the Eastern Tailed-blues aren't close relatives of the swallowtails, another reason they don't have "swallowtail" in their name.

Comments

Popular posts from this blog

Northern Watersnake

Female Brown-headed Cowbird

Rooftop Turkey Vultures