A Common Baskettail dragonfly (Epitheca cynosura) was spotted at Painted Turtle Pond during a photowalk around Occoquan Bay National Wildlife Refuge (OBNWR), Prince William County, Virginia USA. This individual is a late-stage emergent teneral female.
I photographed the process of emergence from the first sighting to the time when the teneral dragonfly flew away: I shot 23 photos in approximately 16 minutes; time is compressed by showcasing six (6) select photos taken at major milestones during the event.
The following photo is the first image from a time-series documenting the emergence of the teneral female. Elapsed time is expressed in hh:mm:ss format, e.g., 00:00:00 is the time when I spotted the emergent teneral female, and 00:16:08 is the total elapsed time.
13 APR 2016 | 11:38:41 am EDT | Elapsed time: 00:00:00
Notice the drop of fluid at the tip of the abdomen. Emerging dragonflies pump fluid into their wings, causing the wings to expand. Next, the same fluid is withdrawn from the wings and used to expand the abdomen. Excess fluid is expelled afterward.
13 APR 2016 | 11:40:48 am EDT | Elapsed time: 00:02:07
The next photo shows the first time the wings opened.
13 APR 2016 | 11:48:55 am EDT | Elapsed time: 00:10:14
Then the wings closed again and remained closed for a while.
13 APR 2016 | 11:51:02 am EDT | Elapsed time: 00:12:21
The wings reopened a few minutes later. Notice that several wings are malformed slightly.
13 APR 2016 | 11:54:14 am EDT | Elapsed time: 00:15:33
Finally, the wings open up, and very soon the teneral adult flies away. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 468). Princeton University Press. Kindle Edition.
The teneral female dragonfly flew away immediately after the last photo in the time-series.
13 APR 2016 | 11:54:46 am EDT | Elapsed time: 00:16:08
This individual is a female, as indicated by her cerci (superior appendages) and thick abdomen. Common Baskettail females have shorter cerci and a thicker abdomen than males of the same species.
Exuviae (in situ)
Several dragonfly exuviae were spotted at Painted Turtle Pond; it’s possible they are cast skins from Common Baskettail. More later after the exuviae are identified using a dichotomous key for dragonfly larvae.
These exuviae are not the one from which the teneral female featured in this post emerged.
Copyright © 2017 Walter Sanford. All rights reserved.