Posts Tagged ‘Clubtail Family’

Deadly Cobras!

August 29, 2016

Several Cobra Clubtail dragonflies (Gomphus vastus) were spotted during a photowalk along the Potomac River at Riverbend Park, Fairfax County, Virginia USA.

Cobra Clubtail seems to be a voracious predator. Three individuals were observed eating smaller insects.

Male 1

The first individual is a male, as indicated by his terminal appendages. He is eating a Crane Fly.

Male 2

Another male was observed eating a small butterfly, possibly an Eastern Tailed-blue (Cupido comyntas).

Female

The last individual is a female, as indicated by her terminal appendages and the rounded shape of its hind wings. She is eating an unknown species of damselfly (female).

Copyright © 2016 Walter Sanford. All rights reserved.

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Everyone’s gotta eat!

August 27, 2016

Several Eastern Ringtail dragonflies (Erpetogomphus designatus) were spotted during photowalks along the Potomac River at Riverbend Park.

Eastern Ringtail seems to be a voracious predator, based upon an admittedly small sample size. Two individuals were observed eating smaller insects.

Male

The first individual is a male, as indicated by his terminal appendages; he is feeding upon an unknown black winged insect.

Female

The last individual is a female, as indicated by her terminal appendages; she is eating an unknown species of damselfly.

Almost gone, except for several legs!

Editor’s Note: The title of this post is an homage to Laura Lecce, a regular reader of my photoblog. Thanks for the inspirational comment on one of my previous posts, Laura!

Copyright © 2016 Walter Sanford. All rights reserved.

More Eastern Ringtail dragonflies

August 19, 2016

One female and two male Eastern Ringtail dragonflies (Erpetogomphus designatus) were spotted during a follow-up photowalk along the Potomac River at Riverbend Park.

Female and male Eastern Ringtail are somewhat similar in appearance. Terminal appendages, the shape of their hind wings, and the relative size of their club are good field markers to differentiate specimens by gender.

Female

The first individual is a female, as indicated by her terminal appendages. Female dragonflies have a pair of cerci (superior appendages) that have little or no function.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

08 AUG 2016 | Riverbend Park | Eastern Ringtail (female)

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

The preceding dorsal view of the dragonfly shows its hind wings are rounded near the body, a good field marker for female clubtail dragonflies. In contrast, the hind wings of male clubtails are “indented.” Also notice the female “club” is slightly smaller than the male club, as shown in the following photos.

Male 1

The male’s abdomen is slightly thinner (shown below); the female’s abdomen is slightly thicker (shown above).

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

08 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

Male 2

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”).

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male, perching in the obelisk position.

08 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

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

Notice the male’s hind wings are “indented” near the body, as shown in the last two photos.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

08 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

08 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

Related Resources: Digital Dragonflies, presenting high-resolution digital scans of living dragonflies.

  • Genus Erpetogomphus | Erpetogomphus designatus | Eastern Ringtail | female | top view
  • Genus Erpetogomphus | Erpetogomphus designatus | Eastern Ringtail | female | side view
  • Genus Erpetogomphus | Erpetogomphus designatus | Eastern Ringtail | male | top view
  • Genus Erpetogomphus | Erpetogomphus designatus | Eastern Ringtail | male | side view

Copyright © 2016 Walter Sanford. All rights reserved.

More Black-shouldered Spinyleg dragonflies

August 17, 2016

Another female and male Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) were spotted during a follow-up photowalk along the Potomac River at Riverbend Park.

Female and male Black-shouldered Spinyleg are somewhat similar in appearance. Terminal appendages, the shape of their hind wings, and the relative size of their club are good field markers to differentiate specimens by gender.

Female

The first individual is a female, as indicated by her terminal appendages. Female dragonflies have a pair of cerci (superior appendages) that have little or no function.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

08 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

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

The preceding dorsal view of the dragonfly shows its hind wings are rounded near the body, a good field marker for female clubtail dragonflies. In contrast, the hind wings of male clubtails are “indented.” Also notice the female “club” is slightly smaller than the male club, as shown in the following photos.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

08 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

08 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

08 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

Male

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”).

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

Although the preceding photo seems to show four terminal appendages, do not be misled! The epiproct for Black-shouldered Spinyleg is essentially a wide plate with two prongs.

Notice the male’s middle leg (on the right side, facing forward) is shorter than either its front- or hind leg. I’m not sure whether the middle leg is malformed, or the result of an injury. Whatever the cause, it might explain why the dragonfly was especially skittish.

Related Resources: Digital Dragonflies, presenting high-resolution digital scans of living dragonflies.

  • Genus Dromogomphus | Dromogomphus spinosus | Black-shouldered Spinyleg | male | top view
  • Genus Dromogomphus | Dromogomphus spinosus | Black-shouldered Spinyleg | male | side view

Copyright © 2016 Walter Sanford. All rights reserved.

Eastern Ringtail dragonfly (female)

August 15, 2016

An Eastern Ringtail dragonfly (Erpetogomphus designatus) was spotted during a photowalk along the Potomac River at Riverbend Park. This individual is a female, as indicated by her terminal appendages and the shape of its hind wings.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (female)

The following dorsal view of the same dragonfly shows its hind wings are rounded near the body, a good field marker for female clubtail dragonflies.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (female)

Copyright © 2016 Walter Sanford. All rights reserved.

Eastern Ringtail dragonflies (males)

August 13, 2016

Eastern Ringtail dragonfly (Erpetogomphus designatus) is a new species on my life list of odonates.

The following photos show the first one that I spotted during a photowalk along the Potomac River at Riverbend Park. This individual is a male, as indicated by his terminal appendages.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

Like all male clubtail dragonflies, its hind wings are “indented” near the body; this distinctive field marker isn’t shown well by any of the photos in this gallery.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

Another male was spotted near the same location, one of several Eastern Ringtails seen perching either on or near the boat ramp at the park.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male, perching in the obelisk position.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

I love a good head-tilt, or two!

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

The last photo shows a male Eastern Ringtail perching on a grassy area alongside the boat ramp.

An Eastern Ringtail dragonfly (Erpetogomphus designatus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

04 AUG 2016 | Riverbend Park | Eastern Ringtail (male)

Copyright © 2016 Walter Sanford. All rights reserved.

Black-shouldered Spinyleg (male)

August 11, 2016

Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) is a new species on my life list of odonates. This is the first one that I spotted during a photowalk along the Potomac River at Riverbend Park.

This individual is a male, as indicated by its terminal appendages and the shape of its hind wings.

Bright yellow juveniles turn pale olive with age. Source Credit: Black-Shouldered Spinyleg, Dragonflies of Northern Virginia, by Kevin Munroe.

Contrast the size of the “club” at the tip of male’s abdomen with the female club, shown in my last photoblog post. Notice the male club is slightly larger than the female club.

The following dorsal view of the dragonfly shows its hind wings are “indented” near the body, a good field marker for male clubtail dragonflies. In contrast, the hind wings of female clubtails are rounded.

Black-shouldered Spinyleg is the only clubtail with broad, pale green thoracic stripes. Also notice the broad dark stripe on the “shoulder” of the thorax, hence the common name “Black-shouldered.” Although all dragonflies have spiny legs, Black-shouldered Spinyleg has large leg spines, especially on their hind legs.

Copyright © 2016 Walter Sanford. All rights reserved.

Black-shouldered Spinyleg (female)

August 9, 2016

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) was spotted during a photowalk along the Potomac River at Riverbend Park. This individual is a female, as indicated by its terminal appendages and the shape of its hind wings.

Now you see it, now you don’t.

The first photo set shows the female dragonfly eating what appears to be a teneral damselfly.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female, eating a damselfly.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

Dragonflies have two small antennae on their face, located in front of their large compound eyes. Zoom in on the full-size version of the following photo. Notice there is a small drop of water surrounding the antenna located in front of the left eye; the water droplet isn’t visible in the first photo.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female, eating a damselfly.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

The Backstory: The dragonfly was perching on a narrow beach along the river. In order to move into position for a lateral view of the dragonfly, I had to wade in the muddy river. Almost immediately I stepped in a seemingly bottomless hole. My left foot sank quickly into mud that would have been over the top of my knee-high rubber boot, so I jerked my foot out of the mud; the sudden motion created a big splash of water that landed in front of the dragonfly. Much to my amazement, the dragonfly didn’t move! I didn’t notice the water drop until I edited this photo set.

The water drop is still visible in the next photo. The damselfly is gone except for its wings and part of a leg.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female, eating a damselfly.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

By the time the dragonfly moved to a nearby perch, the water drop on its face had evaporated.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female, eating a damselfly.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

Perching on vegetation

The following dorsal view of the same dragonfly shows its hind wings are rounded near the body, a good field marker for female clubtail dragonflies.

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

The last photo shows a lateral view of the dragonfly. Look closely at the side of its thorax. Black-shouldered Spinyleg is the only clubtail with broad, pale green thoracic stripes. Also notice the broad dark stripe on the “shoulder” of the thorax, hence the common name “Black-shouldered.”

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | Black-shouldered Spinyleg (female)

Copyright © 2016 Walter Sanford. All rights reserved.

Identifying clubtails by the calendar

June 30, 2016

Much to my surprise, a Lancet Clubtail dragonfly (Gomphus exilis) was spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR), Fairfax County, Virginia USA. This individual is a male, as indicated by his terminal appendages.

A Lancet Clubtail dragonfly (Gomphus exilis) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

26 JUN 2016 | JMAWR | Lancet Clubtail (male)

Ashy Clubtail (Gomphus lividus) and Lancet Clubtail (Gomphus exilis) are two species of dragonflies from the Family Gomphidae (Clubtails) that are similar in appearance.

A Lancet Clubtail dragonfly (Gomphus exilis) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

26 JUN 2016 | JMAWR | Lancet Clubtail (male)

Kevin Munroe, author of the excellent Dragonflies of Northern Virginia Web site, explains how to identify Ashy Clubtail versus Lancet Clubtail on the page for Ashy Clubtail (see the section entitled “Notes from the field”). In this case, item No. 5 explains how to use a calendar to differentiate the two species.

Lastly, use the calendar: April = Ashy Clubtail; June or July = Lancet Clubtail; May = could be either one. (These dates work in Northern Virginia.) Source Credit: Ashy Clubtail, by Kevin Munroe.

Since the specimen shown in the preceding photographs was spotted on 26 June, Lancet Clubtail is almost certainly the correct identification. Further, the physical characteristics described in item No. 3 on Kevin’s checklist confirms what the calendar tells us.

Copyright © 2016 Walter Sanford. All rights reserved.

Dragonhunter dragonfly (female)

June 24, 2016

I’ve spent a lot time looking for Dragonhunter dragonflies (Hagenius brevistylus) in their preferred habitat with limited success. Imagine my surprise and delight when I spotted one in a less than ideal habitat! I could tell you where I found the Dragonhunter, but then I’d have to give you a cyanide capsule, so let’s just call the location “Northern Virginia.”

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

This individual is a female, as indicated by her terminal appendages. Thanks to Michael Moore, member extraordinaire of the Southeastern Odes Facebook group, for verifying my tentative identification.

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

I love a good head-tilt. This girl has a grill as big as a Mack truck!

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

A Dragonhunter dragonfly (Hagenius brevistylus) spotted at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. This individual is a female.

21 June 2016 | Dragonhunter dragonfly (female)

Related Resource: Dragonhunter dragonfly exuvia, a blog post by Walter Sanford.

Copyright © 2016 Walter Sanford. All rights reserved.


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