Posts Tagged ‘Phanogomphus exilis’

Lancet Clubtail dragonfly (male)

June 25, 2017

A Lancet Clubtail dragonfly (Phanogomphus exilis) was spotted during a photowalk at “Straight Fork Beaver Ponds,” Highland County, Virginia USA. This individual is a male, as indicated by his terminal appendages and “indented” hind wings.

09 JUN 2017 | Highland County, VA | Lancet Clubtail (male)

This male Lancet Clubtail was spotted at the same location as a male Harpoon Clubtail dragonfly (Phanogomphus descriptus) featured in a previous post. Lancet Clubtail is a relatively widespread species of odonate, in contrast with Harpoon Clubtail.

09 JUN 2017 | Highland County, VA | Lancet Clubtail (male)

Bonus Bug

Look closely at the preceding photo. Did you notice the exuvia from another type of aquatic insect, possibly either mayfly or stonefly? I didn’t see the exuvia when I shot the photo, and missed them again when I post-processed the image. Sometimes I get so focused on the subject that I don’t see the bigger picture.

Tech Tips

The photos were taken using a Fujifilm X-T1 digital camera, Fujinon 55-200mm zoom lens, and Fujifilm EF-X500 shoe mount flash.

Copyright © 2017 Walter Sanford. All rights reserved.

Lancet Clubtail dragonflies (males)

May 14, 2017

At least two Lancet Clubtail dragonflies (Phanogomphus exilis) were spotted during a photowalk along a mid-size stream in Fairfax County, Virginia USA.

03 MAY 2017 | Fairfax County, VA | Lancet Clubtail (male)

These individuals are males, as indicated by their terminal appendages and indented hind wings.

03 MAY 2017 | Fairfax County, VA | Lancet Clubtail (male)

The next photograph was taken at a later time than the first two photos. All of the photos in this post were taken near the same location. Is this another male, or the same one featured in the preceding photos? Who knows?

03 MAY 2017 | Fairfax County, VA | Lancet Clubtail (male)

Lancet Clubtail versus Ashy Clubtail

Lancet Clubtail looks similar to Ashy Clubtail (Phanogomphus lividus). The only way to differentiate the two species with certainty is to examine their external reproductive anatomy; this is impossible unless the specimens are captured and examined in-hand.

Relative size is used sometimes to identify the two species: Lancet Clubtail is slightly smaller than Ashy Clubtail. There are two problems with this method of identification. First, it is virtually impossible to determine the exact size of a specimen in the field unless it is captured and measured. Second, some natural variation in size should be expected among individuals of the same species.

A quick-and-dirty method for differentiating Lancet- and Ashy Clubtails with some degree of certainty is to look at the markings on abdominal segments eight and nine (S8-9). Lancet Clubtail has a “spearpoint” on top of abdominal segment eight (S8) that almost reaches the end of the segment, a wide yellow stripe on top of segment nine (S9), and irregular yellow markings on the sides of segments eight and nine (S8-9).

03 MAY 2017 | Fairfax County, VA | Lancet Clubtail (male)

(See a full-size version of the original photo, without annotation and inset photo of Ashy Clubtail.)

In contrast, Ashy Clubtail has a spearpoint on top of abdominal segment eight (S8) that is less than half the length of the segment, segment nine (S9) may or may not have a pale yellow stripe on top, and the sides of segments eight and nine (S8-9) may or may not have “poorly defined” yellow markings.

03 MAY 2017 | Fairfax County, VA | Ashy Clubtail (male)

(See a full-size version of the original photo, without annotation.)

Coloration is variable among individuals of the same species, so looking at abdominal markings isn’t always a reliable method of identification. In this case, it works beautifully.

Editor’s Note: The word “spearpoint” and the phrase “poorly defined” are descriptors attributed to Dennis Paulson, Dragonflies and Damselflies of the East (Princeton Field Guides). Princeton University Press. Kindle Edition.

Copyright © 2017 Walter Sanford. All rights reserved.

Phanogomphus

April 20, 2017

Two teneral dragonflies were observed near Mulligan Pond during a photowalk at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. I was able to photograph the first one I spotted; the second flew away as soon as I approached it.

This dragonfly is either Ashy Clubtail (Phanogomphus lividus) or Lancet Clubtail (Phanogomphus exilis). Based upon the short, faded yellow markings on the dorsal side of abdominal segments eight and nine (S8-9), this individual is probably an Ashy Clubtail dragonfly. Less reliably, the 18 April date of the spotting also suggests Ashy Clubtail (for Northern Virginia).

18 APR 2017 | JMAWR | Ashy Clubtail or Lancet Clubtail (female)

Both Ashy- and Lancet Clubtail dragonflies were formerly classified as members of the genus Gomphus. Both species were reclassified recently as Phanogomphus. In the world of taxonomic classification, there are “lumpers” and “splitters.” Score one for the splitters!

Notice the first photo shows the wings folded above the abdomen. I spotted the teneral dragonfly when it flew toward me from the pond shoreline. The dragonfly rested in this location for a few minutes before it flew to a new spot (shown below) where it perched briefly with its wings unfolded. The last time I saw the dragonfly, it was flying toward the forest alongside the pond.

The other teneral dragonfly that I saw — “the one that got away” — was perched on the lawn near the walking path around the lake; it flew toward the forest when I moved closer to take some photographs.

18 APR 2017 | JMAWR | Ashy Clubtail or Lancet Clubtail (female)

(See a full-size version of the original photo, without annotation.)

This specimen is a female, as indicated by her rounded hind wings and terminal appendages.

All female dragonflies have two cerci (superior appendages); in contrast all male dragonflies have two cerci and one epiproct (inferior appendage), collectively called “claspers.” Contrast the appearance of the terminal appendages of this female Ashy Clubtail with a male of the same species.

The last photo in the set is a wider view that shows how well-camouflaged the dragonfly was perched on the lawn around the pond.

18 APR 2017 | JMAWR | Ashy Clubtail or Lancet Clubtail (female)

The Backstory

I was surprised to discover a Lancet Clubtail dragonfly near Mulligan Pond during late-June 2016. Knowing that Ashy Clubtails can be found in the same habitats preferred by Lancet Clubtails, I decided to look for Ashy Clubtails at Jackson Miles Abbott Wetland Refuge beginning in mid-April 2017. Apparently Mulligan Pond is a good place for both species, because I spotted two Ashy Clubtails the first time I went looking for them. Ah, if only odonate hunting were always so easy!

Post Update

As far as I know, this is the first record for this species at this location. A new record for Ashy Clubtail (Phanogomphus lividus) at Jackson Miles Abbott Wetland Refuge was submitted to the Odonata Central records database on 22 April 2017.

Copyright © 2017 Walter Sanford. All rights reserved.


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