Beware of dismissive thinking!

An unknown species of teneral baskettail dragonfly (Epitheca sp.), possibly either Common Baskettail (E. cynosura) or Robust Baskettail (E. spinosa), was spotted near a mid-sized pond at the North Tract of Patuxent Research Refuge, Laurel, Maryland USA.

This individual is a female, as indicated by its terminal appendages.

That’s a very wide abdomen, hairy thorax, and cerci as long (if not slightly longer) as S9. I’m fairly confident it’s a Robust Baskettail but I have limited experience with that species. The pattern of dark spots at the wing base is definitive for Robust but I can’t see them well in your picture. Mike Moore’s opinion would he good. Source Credit: Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group.

I consulted Dr. Michael Moore.

It certainly suggests Robust based on the dimensions of the abdomen and the “hairiness” of the thorax but I would really need to see the pattern of black at the base of the hind wings to be sure. Female Commons can be surprisingly fat. Source Credit: Dr. Michael Moore, a professor in the Department of Biological Sciences at University of Delaware and odonate expert extraordinaire. Dr. Moore’s new Web site is a treasure trove of helpful resources.

The reason neither Mike nor Michael can see the definitive field mark on the base of the baskettail dragonfly’s hind wings is because this individual is a late-stage emergent teneral and its wings haven’t opened.

Regardless of the species of dragonfly, emergence is an essentially identical process. See “Related Resources” (below) for a time-series of photographs showing part of the process of emergence for a female Common Baskettail.

The danger of dismissive thinking.

This sighting was another reminder of one of many “Walterisms”: “Don’t be dismissive!” Huh?

During a recent trip to the Patuxent Research Refuge in search of Harlequin Darner (G. furcillata), my good friend Mike Powell and I saw many basktettails, mostly Common Baskettail. Common. That’s the key word. When I noticed several baskettails, I thought, “Oh, Common Baskettails. Nothing to see here, folks. Move along. Must find Harlequin!”

As it turns out, my laser-like focus on finding my first Harlequin Darner might have caused me to miss an opportunity to see a Robust Baskettail — another new species for my life list of odonates. Once again I’m reminded that dismissive thinking can be wrong-headed.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

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