Great Blue Skimmer

Here's yet another blue dragonfly, a Great Blue Skimmer (in the proud footsteps of the Blue Dasher, Eastern Pondhawk, and Slaty Skimmer). Although I've shown one of these before, that was likely a juvenile and really didn't show the blue that inspired their name. 

IMHO this is a dragonfly that, especially when seen at a distance where size is difficult to determine, could be confused with the previously mentioned Blue Dasher. They're both dragonflies (as opposed to damselflies), the males have a light blue pruinose, they have small black stigmas on the front of their wings, and they have white faces. Here are some differences:

  1. Great Blue Skimmers are much larger dragonflies. Individuals vary in size, but you can expect Great Blue Skimmers to be between 20% and 120% bigger than Blue Dashers. (Side by side, you'd easily be able to tell them apart.)
  2. On most Blue Dashers, their pruinose doesn't extend all the way to the end of their abdomen, leaving the tip looking black. Like most other dragonflies, Great Blue Skimmer pruinose usually makes their abdomen completely blue.
  3. The Blue Dasher pruinose is usually at least a brighter shade of blue, sometimes looking whitish. The Great Blue Skimmer has a duller, slatey blue color.
  4. If you can see the front of the head, the eyes of the Great Blue Skimmer are a bright/light blue, while the Blue Dasher's eyes are more like a slightly bluish green.
Careful readers might have noticed I mentioned the slatey colored pruinose of the Great Blue Skimmer and wonder how to distinguish it from the Slaty Skimmer. Here's what I can tell you about that:
  1. Though the Great Blue Skimmer is the larger of the two, the Slaty Skimmer is much closer to them in size compared to the smallish Blue Dasher. Most of the time size won't help you tell them apart.
  2. Usually the Slaty Skimmer has darker pruinose compared to the Great Blue Skimmer. I generally get the sense looking at them that the Great Blue Skimmer is a little too light colored to be a Slaty Skimmer.
  3. If you see a mature Slaty Skimmer's head, it'll look dark, virtually black. That's in sharp contrast to the white-faced, blue-eyed Great Blue Skimmer.
In this first picture you can see most of what I've discussed except for the white face.

August 3, 2022 at Lord Stirling Park
Photo 222580605, (c) jpviolette, some rights reserved (CC BY-NC)

Just so you know I wasn't kidding about the white face (somewhat rare in dragonflies), you can see a little of it in this picture.

August 3, 2022 at Lord Stirling Park
Photo 222581411, (c) jpviolette, some rights reserved (CC BY-NC)


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