Things are not always what they seem

Male Eastern Amberwing dragonflies (Perithemis tenera) are so distinctive in appearance that you can identify them with just a quick glance, right? Maybe; maybe not.

Things are not always what they seem: the first appearance deceives many; the intelligence of a few perceives what has been carefully hidden. Source Credit: Phaedrus.

When I spotted the following Eastern Amberwing dragonfly along Barnyard Run at Huntley Meadows Park, I misidentified it as a male. Truth be told, I always thought its terminal appendages look more female than male, but I allowed myself to be fooled by the reddish-orange coloration of its wings. Turns out this individual is either an andromorph or gynandromorph female.

An Eastern Amberwing dragonfly (Perithemis tenera) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is an andromorph female.

29 JUN 2015 | HMP | Eastern Amberwing (female, gynandromorph)

heteromorph is a female that looks different than a male. An andromorph is a female that resembles a male. A gynandromorph combines both male and female characteristics.

All male dragonflies have three terminal appendages, collectively called “claspers,” that are used to grab and hold female dragonflies during mating: an upper pair of cerci (“superior appendages”) and a lower unpaired epiproct (“inferior appendage”). Female dragonflies have a pair of cerci (superior appendages) that have little or no function.

Look closely at the full-size version of the preceding annotated image. Notice this individual appears to have three cerci. For this reason, Dr. Dennis Paulson hypothesizes this individual may be a gynandromorph.

In contrast, heteromorph female Eastern Amberwings, such as the one shown below, feature two and only two cerci plus mostly clear wings with a variable pattern of wing spots.

An Eastern Amberwing dragonfly (Perithemis tenera) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a female.

05 AUG 2015 | HMP | Eastern Amberwing (female, heteromorph)

After a second look at my photo library, I discovered another possible andromorph/gynandromorph female spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge.

An Eastern Amberwing dragonfly (Perithemis tenera) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is an andromorph female.

24 JUL 2015 | JMAWR | Eastern Amberwing (female, gynandromorph)

Several males were spotted at the same location. Look closely at the full-size version of the preceding and following photos. Notice the difference in appearance between the terminal appendages of the andromorph/gynandromorph female (shown above) and male (shown below).

An Eastern Amberwing dragonfly (Perithemis tenera) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Eastern Amberwing (male)

See? There’s a reason I’m fixated on odonate terminal appendages! Dr. Paulson and I are curious to know whether other naturalists have spotted andromorph/gynandromorph female Eastern Amberwing dragonflies.

Since this post began with a quote from Phaedrus, somehow it seems appropriate it should end with another quote.

The only problem with seeing too much is that it makes you insane. Source Credit: Phaedrus.

Editor’s Note: Sincere thanks to Dennis Paulson for verifying my tentative identification of the andromorph/gyandromorph female Eastern Amberwing dragonfly spotted on 29 June 2015. I was motivated to double-check my initial identification after recently noticing the following quote from one of Dennis’ excellent books.

Very rare andromorph females may have entirely yellow-orange wings as males, with some dark smudging. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 9406-9407). Princeton University Press. Kindle Edition.

Copyright © 2015 Walter Sanford. All rights reserved.

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One Response to “Things are not always what they seem”

  1. Mike Powell Says:

    Fascinating post, Walter. I admit that have never given a second thought to identifying male Eastern Amberwings and I am probably correct most of the time. Your photos and explanation make it clear, though, that there are exceptions. My photos are not well organized enough to do a comprehensive check to see if I have shot any gynandromorphs, but I will look a little more closely at my most recent shots of Eastern Amberwings.

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