Posts Tagged ‘Family Gomphidae (Clubtails)’

Another Common Sanddragon

July 10, 2019

Common Sanddragon dragonfly (Progomphus obscurus) was spotted by my good friend Mike Powell during a photowalk along a small stream in the forest at an undisclosed location in Prince William County, Virginia USA.

This individual is a male, as indicated by his “indented” hind wings and terminal appendages.

21 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

It’s possible the subject is the same male we saw a short distance upstream from this location.

21 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

Adult flight period

According to records for the Commonwealth of Virginia maintained by Dr. Steve Roble, Staff Zoologist at the Virginia Department of Conservation and Recreation, Division of Natural Heritage, the adult flight period for P. obscurus is from May 15 to September 19. The species is classified as common. Its habitat is “sandy streams.”

Bear in mind, Dr. Roble’s records are for the entire state, therefore the adult flight period for P. obscurus seems to be longer than it is in reality. The adult flight period for a single site is probably shorter — more likely around two months. For example, according to records for Northern Virginia maintained by Kevin Munroe, former manager of Huntley Meadows Park, the adult flight period for Commom Sanddragon is 29 May to 06 August.

Cut Banks and Sand Point Bars

Here’s a quick lesson on the geomorphology and basic hydrology of meandering streams, as it relates to odonates such as the Common Sanddragon that Mike and I observed along a small stream in the forest.

Streamflow is faster along cut banks and slower along sand point bars. As a result, erosion occurs along cut banks and deposition occurs along sand point bars.

P. obscurus — like the male featured in this post — can be found perching on sand point bars, usually facing the water.

Source Credit: The preceding image is a file from the Wikimedia Commons, United States Geological Survey.

Tech Tips

The first photo is uncropped, that is, full resolution for the Panasonic Lumix DMC-FZ300 superzoom bridge camera (4,000 x 3,000 pixels). Needless to say, I was fairly close to the subject!

The second photo is cropped in order to eliminate some distracting elements near the edges of the image.

Copyright © 2019 Walter Sanford. All rights reserved.

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Enter Sandman

July 1, 2019

Common Sanddragon dragonfly (Progomphus obscurus) was spotted by my good friend Mike Powell during a photowalk along a small forest stream at an undisclosed location in Prince William County, Virginia USA.

This individual is a male, as indicated by his “indented” hind wings and terminal appendages.

21 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

The Common Sanddragon is perched on a medium size fallen tree in the first photo, and on a boulder in the creek in the last photo. In both photos, the male is perched facing the water — presumably in search of a mate.

21 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

Related Resource: Metallica – Enter Sandman [Official Music Video]

Copyright © 2019 Walter Sanford. All rights reserved.

Dromogomphus spinosus exuvia

June 28, 2019

A dragonfly exuvia was collected by Joe Johnston on 22 May 2019 at Aquia Creek, Stafford County, Virginia USA. This specimen is the cast skin from a Black-shouldered Spinyleg (Dromogomphus spinosus) larva. D. spinosus is a member of Family Gomphidae (Clubtails).

Black-shouldered Spinyleg (Dromogomphus spinosus) | exuvia (dorsal)

At first I thought the exuvia might be a species from the genus Stylurus, based upon the mid-dorsal spine on abdominal segment nine (S9). After careful examination of two excellent photo-illustrated PowerPoint presentations by Kevin Hemeon at NymphFest 2016 (see Related Resources, below), I noticed none of the species in the genus Stylurus have dorsal hooks. That’s when I realized the specimen must be D. spinosus. Eureka!

Related Resources

The following PowerPoint presentations by Kevin Hemeon are available in the “Files” section of the Northeast Odonata Facebook group. Direct links to the documents are provided below.

The Backstory

Joe Johnston is an avid boater and sport fisherman who kindly agreed to be my “Eyes on the Aquia,” always on the lookout for odonate exuvia to share with me. On 22 May 2019 Joe caught a largemouth bass that swam around one of the wooden pilings of a boat dock that extends far into Aquia Creek. The fishing line was snagged on the piling so Joe moved his boat into position to free the fish. That’s when he noticed the exuvia clinging to a piling on the underside of the dock. Good catches, Joe!

Tech Tips

The following equipment was used to shoot the quick-and-dirty handheld macro photograph featured in this post: Fujifilm X-T1 digital camera; and Fujinon XF80mm macro lens plus lens hood. The camera was set for both manual exposure and manual focus. That’s right, a switch on the camera body is used to set the type of focus. It’s a Fujifilm thing. Actually, back-button focus was used to autofocus the image and adjusted manually as necessary. That’s also a Fujifilm thing. Camera settings: focal length 80mm (120mm, 35mm equivalent); ISO 200; f/9; 1/180s.

Godox XProF radio flash trigger, mounted on the hotshoe of my X-T1, was used to control an off-camera Godox TT685 Thinklite TTL Flash (TT685F) set for radio slave mode. The flash was fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the image, plus add annotations.

Sometime in the future (probably the odonate “off-season”) I will create higher quality composite images of this exuvia, shown from all viewpoints including the ventral view. As it turns out, the dorsal view is sufficient to identify this species.

Copyright © 2019 Walter Sanford. All rights reserved.

Black-shouldered Spinyleg (female)

June 26, 2019

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) was spotted by my good friend Mike Powell during a photowalk along a small forest stream at an undisclosed location in Prince William County, Virginia USA.

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

21 JUN 2019 | PNC. Wm. County, VA | Black-shouldered Spinyleg (female)

Notice the broad, mostly black stripe on the shoulder of her thorax, and large spines on the femur — two field marks from which the common name of this species is derived.

21 JUN 2019 | PNC. Wm. County, VA | Black-shouldered Spinyleg (female)

As this relatively young individual matures, its coloration will change from bright yellow to a dull shade of olive green similar to this mature male spotted at another location in Fairfax County, Virginia USA.

The dragonfly is perched on the broad green leaves of skunk cabbage (Symplocarpus foetidus) in both of the preceding photos.

Tech Tips

The first photo is uncropped, that is, full resolution for the Panasonic Lumix DMC-FZ300 superzoom bridge camera (4,000 x 3,000 pixels). Needless to say, I was very close to this cooperative subject!

The second photo is cropped in order to eliminate some leading lines near the edges of the image.

An external flash unit was used for both photos featured in this post. Sometimes other wildlife photographers ask me why I prefer using flash for insect photography. See for yourself by looking at Mike Powell’s photo of the same subject, taken without flash. Although we were literally standing side-by-side when our photos were taken, the difference is striking. Mike’s photo shows the dim ambient light of the place where we photographed the dragonfly better than my photos; in contrast, I prefer to highlight the details of the subject.

Related Resource: Posts Tagged ‘Black-shouldered Spinyleg dragonfly’

Copyright © 2019 Walter Sanford. All rights reserved.

Dragonhunter (female)

June 24, 2019

A Dragonhunter dragonfly (Hagenius brevistylus) was spotted at South Fork Quantico Creek along “South Valley Trail,” Prince William Forest Park, Prince William County, Virginia USA.

21 JUN 2019 | Prince William Forest Park | Dragonhunter (female)

This individual is a female, although it is difficult to see some critical field marks from the viewpoint in the preceding photo. Thanks to Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group, for confirming my tentative identification of the gender.

Copyright © 2019 Walter Sanford. All rights reserved.

Common Sanddragon dragonfly (male)

June 17, 2019

A Common Sanddragon dragonfly (Progomphus obscurus) was spotted by my good friend Mike Powell during a photowalk along a small forest stream at an undisclosed location in Prince William County, Virginia USA.

I was standing in the creek looking toward the sandy shoreline where the Common Sanddragon was perching.

14 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

This individual is a male, as indicated by his “indented” hind wings and terminal appendages.

14 JUN 2019 | PNC. William County, VA | Common Sanddragon (male)

Both of the photos featured in this blog post are uncropped, that is, full resolution for the Panasonic Lumix DMC-FZ300 superzoom bridge camera (4,000 x 3,000 pixels).

Copyright © 2019 Walter Sanford. All rights reserved.

Composite image: “Generic Gomphid” (face)

February 27, 2019

larva/nymph in the Family Gomphidae (Clubtails) was collected by Bob Perkins from the New River in southwestern Virginia. The larva died before it metamorphosed into an adult.

“Generic Gomphid” larva (preserved specimen) | New River, VA USA

An Ashy Clubtail dragonfly nymph was also collected by Bob Perkins. (The date and location where the specimen was collected are unknown.) The nymph was reared in captivity until it emerged on 21 March 2017 and metamorphosed into an adult female. This specimen is the exuvia from the nymph.

Although face-head of the “Generic Gomphid” and Ashy Clubtail look similar, they aren’t identical. More later after the specimen is keyed out carefully.

Related Resources

Tech Tips

13 photos were used to create the focus stack of the “Generic Gomphid.” A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

The following equipment was used to shoot the composite image of the “Generic Gomphid”: Canon EOS 5D Mark II digital camera, in manual mode; Canon MP-E 65mm Macro lens (set for f/11 at ~2.5x); a Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and a single external flash set for “Slave” mode — a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and external flash units.

Adobe Photoshop CC 2017 was used to create the focus stack, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Composite images: “Generic Gomphid”

February 13, 2019

“It’s like Deja vu all over again.” (Source Credit: Yogi Berra.) But seriously folks, if you were thinking “Hey these pictures look familiar!” then you’re right. My last blog post features “one-offs” of the same subject, that is, photos with a single focus point on the mid-body of the specimen.

This post features focus-stacked composite images that show dorsal- and ventral views of a preserved larva in the Family Gomphidae (Clubtails) that was collected by Bob Perkins. I think both composite images look better than the “one-offs” in my last blog post; the difference is especially noticeable by looking at the head and tail in the vernal view.

Dorsal

Five (5) photos were used to create the first focus stack. A single focus point was positioned over select anatomical features; photos were taken at each point of interest.

“Generic Gomphid” larva (preserved specimen) | New River, VA USA

Ventral

Six (6) photos were used to create the second focus stack.

“Generic Gomphid” larva (preserved specimen) | New River, VA USA

Related Resources

Tech Tips

The following equipment (shown below) was used to shoot the preceding photos: Fujifilm X-T1 digital camera; Fujifilm MCEX-16 extension tube; Fujinon XF80mm macro lensGodox XProF TTL Wireless Flash Trigger for Fujifilm camerasGodox TT685F Thinklite TTL Flash for Fujifilm CamerasGodox TT685C Thinklite TTL Flash for Canon Cameras fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier; and a Canon 580EX II Speedlite mounted on a Godox X1R-C TTL Wireless Flash Trigger Receiver for Canon. A new Godox TT685O Thinklite TTL Flash for Olympus/Panasonic Cameras was added to an array of radio-controlled external flash units used to light the specimen. All flashes were set for Manual Mode at 1/128 power.

Adobe Photoshop CC 2017 was used to create the preceding focus-stacked composite images, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.

Test shots: “Generic Gomphid”

February 11, 2019

A larva/nymph in the Family Gomphidae (Clubtails) was collected by Bob Perkins from the New River in southwestern Virginia. The larva died before it metamorphosed into an adult.

Test shots of this beautifully preserved specimen were taken using a small-ish aperture of f/11 for greater depth of field. The following photos are “one-offs,” that is, not composite images.

Dorsal

80mm (120mm, 35mm equivalent) | ISO 200 | f/11 | 1/180 s | 0 ev

Bob’s best guess of the identity of the specimen is Phanogompus sp. I see several similarities between this larva and a Phanogomphus lividus exuvia (Ashy Clubtail) in my collection, so Bob’s tentative identification might be correct. More later after the specimen is keyed out.

Ventral

80mm (120mm, 35mm equivalent) | ISO 200 | f/11 | 1/180 s | 0 ev

This individual might be female, as indicated by the rudimentary ovipositor that can be seen on the ventral side of the specimen along the boundary between abdominal segments eight and nine (S8-9).

Related Resources

Tech Tips

The following equipment (shown below) was used to shoot the preceding photos: Fujifilm X-T1 digital camera; Fujifilm MCEX-16 extension tube; Fujinon XF80mm macro lensGodox XProF TTL Wireless Flash Trigger for Fujifilm camerasGodox TT685F Thinklite TTL Flash for Fujifilm CamerasGodox TT685C Thinklite TTL Flash for Canon Cameras fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier; and a Canon 580EX II Speedlite mounted on a Godox X1R-C TTL Wireless Flash Trigger Receiver for Canon. A new Godox TT685O Thinklite TTL Flash for Olympus/Panasonic Cameras was added to an array of radio-controlled external flash units used to light the specimen. All flashes were set for Manual Mode at 1/128 power.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen the final output.

Gear used for studio macro photography.

By the way, in case you looked at the preceding photo and wondered “What’s up with the crazy crop?” I used Photoshop to conceal some of the clutter in my kitchen. I set up my macro photo rig in the kitchen because it’s the largest uncarpeted area in my tiny apartment. Padded carpet is a poor surface for macro photography — the field of view from a tripod-mounted camera-lens-flash trigger combo shifts noticeably (and unacceptably) as one moves around the rig.

Copyright © 2019 Walter Sanford. All rights reserved.

Focus-stacking with CamRanger

January 7, 2019

This blog post reports the result of more experimentation with completely automated focus stacking using CamRanger.

25 photos were used to create this focus-stacked composite image of an Eastern Least Clubtail dragonfly (Stylogomphus albistylus) exuvia from an odonate nymph that Bob Perkins collected and reared.

I own two Canon macro lenses: a Canon MP-E 65mm Macro lens; and a Canon EF100mm f/2.8L Macro lens.

The MP-E 65mm macro is manual focus only, and cannot be used with CamRanger to create automated focus-stacked composite images.

In contrast, the EF100mm macro can be used with CamRanger to create automated focus stacks. In order to increase the magnification of the EF100mm macro, I used the lens in combination with three Kenko macro automatic extension tubes: 12mm; 20mm; and 36mm.

Pros and Cons

My goal was to create a tight close-up showing the face-head only. On one hand I failed to achieve my goal due to less maximum magnification using the combination of EF100mm macro lens and extension tubes rather than the MP-E 65mm macro lens.

On the other hand I shot 25 photos in a little more than four minutes*, with the focus plane shifted in small increments from front to back along the subject — all without touching the camera after setting the initial focus point. That’s what I call success!

Related Resources

Tech Tips

The following equipment was used to shoot all of the photographs for the focus-stacked composite image of the exuvia: CamRanger hardware, and iOS app running on my iPad mini (with retina display); Canon EOS 5D Mark II digital camera, in manual mode; Kenko macro automatic extension tubes (12mm, 20mm, and 36mm)Canon EF100mm f/2.8L Macro lens (set for manual focus); and Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and several external flashes set for “Slave” mode including Canon 580 EX- and Canon 580EX II Speedlites and a Godox TT685C Thinklite TTL Flash fitted with a Lastolite Ezybox Speed-Lite 2 flash modifier.

Auto power-off was disabled for the camera and all external flash units. CamRanger was set for a *10-second delay between shots in order to allow sufficient time for the lens to change focus automatically, the camera rig to settle, and the flash units to power-cycle.

Adobe Photoshop CC 2017 was used to create the focus-stacked composite image, as well as spot-heal and sharpen the final output.

Copyright © 2019 Walter Sanford. All rights reserved.


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