Dragonfly emergence from birdbath

[Lisa Millbank]

I was surprised to find the shed exoskeleton of some type of dragonfly near our water feature/birdbath last week.  It was about 27mm long, and looks like it may have come from some type of skimmer (maybe a Common Whitetail?), see attachment.  If anyone can suggest what species this is, I'd appreciate it.

The water feature didn't seem very suitable for dragonfly naiads due to scarce insect prey.  I finished most of it and turned it on early last fall, when it had nothing but gravel and tap water in it.  Most of the information I could find indicates that dragonflies usually produce one generation per year, so the egg probably would have been laid around that time.  But, maybe there are exceptions to that.

We noticed just a few aquatic insects, including a backswimmer and some mosquito-type larvae in the pond, which mysteriously disappeared.  That should have been a clue that a little carnivorous beast was lurking within the depths of the gravel.

A few weeks ago we observed a pair of Vivid Dancers laying eggs near a monkeyflower plant, so there could be some little damselfly naiads in there now.  The only other odonates we've seen lingering around the water feature are Common Whitetails and Flame Skimmers.

Lisa Millbank

[Jim Johnson]

Hi Lisa,

That appears to be one of the Pantala—most likely Spot-winged Glider, P. hymenaea, since that is the more abundant/regularly occurring of the two species in the Northwest.

Did you keep the exuvia? There are not many records of Pantala completing development in this region. It appears that the nymphs are unable to survive the winters, and the few we have were surely laid by adults earlier in the late spring/early summer. Pantala nymphs are among the quickest to complete development and emerge. 

If you have the exuvia (or others), I’d like to receive them to confirm the record. And look for others. A couple years ago, about 70 P. hymenaea emerged from a backyard pond in Jackson Co. over a period of a couple weeks. 

Jim Johnson

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[Lisa Millbank]

Thank you Jim,

We expected it to be a much more common species than that!  That's really interesting that a tiny backyard pond would be attractive to Pantala species.  I went out to look for more exuviae and didn't find any.  However, I do still have the original one and would be happy to mail it to you.

Lisa

[Jim Johnson]

Great! They do seem to be fond of backyard water features (if not heavily vegetated) as well as things like open water tanks and unvegetated stock ponds. It probably relates to their natural preference for temporary ponds created by thunderstorms on the deserts and plains.

Maybe keep an eye out for a few more days, and look carefully in the pond—you might spot nymphs if they’re in there.

When you’re ready, you can send the exuviae to:

3003 Unander Avenue

Vancouver, WA 98660

Thanks!

Jim