Posts Tagged ‘Virginia’

Flashback to late-May 2019

September 16, 2019

Look closely at the following photo — there’s a dragonfly in there somewhere!

21 May 2019 | PNC. William County, VA | Lancet Clubtail (female)

A Lancet Clubtail dragonfly (Phanogomphus exilis) was spotted by Gary Myers at an undisclosed location in Prince William County, Virginia USA. The dragonfly is perched on leaf litter in a seepage area upstream from a small pond.

Female and male terminal appendages

This individual is a female, as indicated by her rounded hind wings and terminal appendages. (Notice the “bonus bug” to the right of the label for cercus.)

21 May 2019 | PNC. William County, VA | Lancet Clubtail (female)

Contrast the appearance of those female field marks with males of the same species.

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

Related Resource: Odonate Terminal Appendages — single-topic field guides for dragonflies and damselflies featuring both text and annotated photos.

Copyright © 2019 Walter Sanford. All rights reserved.

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“Grays” love them some me!

August 14, 2019

2019 was a record-setting year for observing Gray Petaltail dragonflies (Tachopteryx thoreyi) with Mike Powell at an undisclosed location in Prince William County, Virginia USA.

  • 21 May 2019 was the day that we observed at least a dozen (12+) Gray Petaltail — the most on any day during 2019.
  • 14 June 2019 was the day that the most “Grays” landed on me, including one female and two males plus some others that didn’t perch long enough to be photographed by either Mike or me.

Female

The first individual is a female, as indicated by her rounded hind wings and terminal appendages. She is perched on the front of my gray-green shirt.

Photo used with permission from Mike Powell.

Please get this man to a barber STAT! On the other hand, there isn’t much else that can be done about the face. As you can see, I’m the owner of a high mileage “vehicle” — fortunately it still runs good!

Photo used with permission from Mike Powell.

Males

The next individual is a male, as indicated by his “indented” hind wings, and terminal appendages. He is perched on the right sleeve of my shirt.

Photo used with permission from Mike Powell.

The same male is shown in the following image. This photo is my favorite in the gallery.

Photo used with permission from Mike Powell.

The last individual, possibly/probably a male, is perched on my off-white bucket hat. The “Gray” was doing a Vulcan mind-meld with me by using specialized contact via the tips of his legs.

Photo used with permission from Mike Powell.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

More “Grays” on me

August 12, 2019

Well, really just one “Gray.” Gray Petaltail dragonfly (Tachopteryx thoreyi), that is. Perched on my … er, hip. This individual is a female, as indicated by her rounded hind wings and terminal appendages.

Guest photographer Michael Powell shot both images during a photowalk with me on 21 May 2019 at an undisclosed location in Prince William County, Virginia USA.

The following photo set provides a brief example of what we call “working the shot.” The first photo is what some other ode hunters call the “record shot,” meaning get a shot, any shot of the subject in case it flies away and is never seen again.

Photo used with permission from Mike Powell.

Slowly Mike moved closer to get the shot he wanted, shown below.

Photo used with permission from Mike Powell.

The Backstory

21 May 2019 was a great day for spotting Gray Petaltail dragonflies during a long, productive photowalk with Michael Powell at two locations: along a small stream in the forest; and around a small seep-fed pond. At least a dozen (12+) T. thoreyi were observed during the day, including two “Grays” that landed on Mike.

As we were walking toward Mike’s car at the end of the day, I was feeling disappointed that we hadn’t taken any photos of T. thoreyi perched on me. That’s when I noticed a Gray Petaltail perched on a fence rail. Before I was able to take a picture of the dragonfly, she flew from the fence rail to a new perch on my backside. Fortunately Mike was close behind me and was able to shoot the good photos featured in this blog post. Needless to say, I suffered as the butt of many jokes related to my indelicate circumstance!

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Odonate exuviae collecting sites

July 29, 2019

The following video shows a “boater’s-eye view” of some sites where odonate exuviae have been collected by Joseph Johnston along Aquia Creek, located in Stafford County, Virginia USA. Joe 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.

The first photo gallery features still images of several spots shown in the preceding video. Joe estimates the water is ~5-6 feet deep outside the channel markers, and much deeper in the middle of the creek.

Joe’s boat is somewhere between the long boat docks (lower-right quadrant) and Government Island (near center), as shown in an aerial view of Aquia Creek provided by Google Maps.

The last photo gallery features still images of several exuviae, shown in situ before Joe collected the specimens. The first photo shows where it all began, when Joe collected his first dragonfly exuvia for me on 20 June 2018.

Related Resources

Credits

All media Copyright © 2019 by Joseph Johnston. Used with permission from Mr. Johnston.

Copyright © 2019 Walter Sanford. All rights reserved.

You look like a tree to me!

May 22, 2019

Gray Petaltail dragonflies (Tachopteryx thoreyi) have a well-known preference for perching on gray or tan colored surfaces, including gray or tan colored clothing. Dressed appropriately, Mike Powell and I visited a hotspot for Gray Petaltail where we hoped to shoot some photographs of T. thoreyi perched on each other.

The first individual is a female, perched on the front of Mike Powell’s gray sweatshirt.

21 MAY 2019 | Northern Virginia | Gray Petaltail (female)

The last individual is a male, perched on Mike Powell’s left shoulder.

21 MAY 2019 | Northern Virginia | Gray Petaltail (male)

I’m guessing the dragonflies were thinking, “Hey Mike, you look like a tree to me!” No offense intended, good buddy. In fact, I think you should be flattered that these spectacular specimens befriended you!

Copyright © 2019 Walter Sanford. All rights reserved.

Test shots: Aeshna umbrosa exuvia

December 3, 2018

Bob Perkins collected and reared an unknown species of odonate nymph from a tiny stream in Carroll County, Virginia USA. The larva emerged from one of Bob’s holding tanks overnight on 23-24 November 2018 and metamorphosed into an adult male Shadow Darner dragonfly (Aeshna umbrosa). Shadow Darner is a member of the Family Aeshnidae (Darners). The following test shots show the exuvia from the odonate nymph.

Test shots of this beautiful specimen were taken using a relatively small aperture of f/16 for greater depth of field. Each photo is a “one-off,” that is, not a composite image. Focus stacks will be created sometime in the near future, after the exuvia is rehydrated and its legs are repositioned  for easier posing.

Lateral-ventral view

The focus point of the first photo is on the right eye. Given the orientation of the specimen, most of the exuvia is acceptably in focus at f/16. For what it’s worth, I really like the composition of this photo!

Notice the specimen has a flat labium (prementum) that doesn’t cover the face (not mask-like). That is a characteristic field mark of two families of dragonflies: Family Aeshnidae (Darners); and Family Gomphidae (Clubtails).

Shadow Darner (Aeshna umbrosa) | exuvia (lateral-ventral)

This individual is a male, as indicated by vestigial hamules that are visible on the ventral side of the specimen.

Dorsal view

The focus point of the next photo is on the head: the head is tack-sharp; the terminal appendages are in soft-focus. Sometimes it’s necessary to create focus-stacked composite images in order to render the subject in focus from head-to-tail and edge-to-edge.

Lateral spines on abdominal segments six to nine (S6-9) indicate this specimen is A. umbrosa.

The focus point of the next photo is on the abdomen, just below the wing pads. Relative to the preceding photo, notice the head is slightly softer in focus while the terminal appendages are slightly sharper in focus.

Tech Tips

The following equipment was used to shoot all of the preceding photographs: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon 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.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen all three images.

Copyright © 2018 Walter Sanford. All rights reserved.

Test shots: Tachopteryx thoreyi exuviae

November 30, 2018

Two Gray Petaltail dragonfly (Tachopteryx thoreyi) exuviae were collected on 23 May 2018 by Walter Sanford near a forest seep at an undisclosed location in Northern Virginia USA. Gray Petaltail is a member of the Family Petaluridae (Petaltails).

Although both specimens are similar, they aren’t identical. For example, twin rows of hook-like structures are clearly visible on the dorsal side of the abdomen on the lower exuvia, and almost invisible on the upper exuvia. The upper exuvia is dirtier and appears to be more “worn” than the lower one. Notice the “schmutz” on the face of the lower exuvia, probably a piece of leaf litter.

Both individuals might be male, as indicated by vestigial hamules that appear to be visible on the ventral side of the specimens.

Test shots of the specimens were taken using a relatively small aperture of f/16 for greater depth of field. Each photo is a “one-off,” that is, not a composite image. Focus stacks will be created sometime in the near future, after the exuviae are rehydrated, cleaned, and posed for better composition.

Tech Tips

The following equipment was used to shoot both of the preceding photographs: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon 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.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen both images.

Copyright © 2018 Walter Sanford. All rights reserved.

Test shots: Stylurus sp. exuvia

November 23, 2018

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 18 July 2018, Joe collected an especially interesting specimen from Aquia Creek in Stafford County, Virginia USA.

Abdominal segment nine (S9) is elongated, strongly suggesting this individual is a member of the genus Stylurus (Hanging Clubtails).

Stylurus sp. | exuvia (dorsal)

Did you notice the spider carcass that photobombed my test shots of the exuvia? Look for the spider along the upper-edge of the thorax in the dorsal view; lower-edge in the ventral view.

Stylurus sp. | exuvia (ventral)

This individual might be Laura’s Clubtail (Stylurus laurae). Laura’s Clubtail is within range of Stafford County, although it is unknown to occur there. S. laurae would be a new species for the Dragonfly Society of the Americas Odonata Central species checklist for Stafford County, Virginia USA.

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 Laura’s Clubtail is 20 June to 26 September. The species is rare to uncommon. Its habitat is streams and rivers.

Tech Tips

The following equipment was used to shoot both of the macro photographs featured in this post: Fujifilm X-T1 digital camera; Fujifilm MCEX-11 extension tube; 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); f/16; 1/500s.

Godox XProF radio flash trigger, mounted on the hotshoe of my X-T1, was used to control a pair of off-camera Godox TT685 Thinklite TTL Flashes (TT685F and TT685C) set for radio slave mode. Each flash was fitted with a snap-on plastic diffuser.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen both images.

Copyright © 2018 Walter Sanford. All rights reserved.

Test shots: Stylurus plagiatus exuvia

November 21, 2018

A Russet-tipped Clubtail (Stylurus plagiatus) exuvia was collected by Joe and Loren Johnston on 20 June 2018 from Aquia Creek in Stafford County, Virginia USA.

Notice that abdominal segment nine (S9) is elongated, strongly suggesting this individual is a member of the genus Stylurus. The large dorsal hook of abdominal segment nine (S9) that overhangs segment 10 (S10) is a key marker for southern specimens of plagiatus.

The “working distance” for the 11mm Fujifilm extension tube/Fujinon 80mm macro lens combo, that is, the distance from the front of the lens barrel to the subject, is long enough to be able to use the lens hood.

Hotspots from external flash units, technically known as specular highlights, are more noticeable sometimes when the flash heads are closer to the subject. It appears the lens hood may have reduced that problem; more experimentation is required to be sure.

Related Resource: Stylurus plagiatus exuvia, a photo-illustrated identification guide.

The Backstory

Joe Johnston is an avid boater and sport fisherman. On 20 June 2018, Joe and his brother Loren were fishing together on Aquia Creek in Stafford County, Virginia USA.

Fish require food and shelter. Sometimes fish shelter near trees that have fallen into water, or the wooden pilings of boat docks. Joe and Loren were casting artificial fishing lures toward one of several docks that extend far into Aquia Creek, when Loren’s lure snagged on one of the pilings. When Joe moved his boat alongside the piling in order to retrieve the fishing lure, Loren noticed an odonate exuvia on the side of the piling. Joe and Loren kindly collected several exuviae, including this one, and shared them with me. Thanks, gentlemen!

Tech Tips

The following equipment was used to shoot both of the macro photographs featured in this post: Fujifilm X-T1 digital camera; Fujifilm MCEX-11 extension tube; 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); f/16; 1/500s.

Godox XProF radio flash trigger, mounted on the hotshoe of my X-T1, was used to control a pair of off-camera Godox TT685 Thinklite TTL Flashes (TT685F and TT685C) set for radio slave mode. Each flash was fitted with a snap-on plastic diffuser.

Adobe Photoshop CC 2017 was used to spot-heal and sharpen both images.

Copyright © 2018 Walter Sanford. All rights reserved.

Macromia alleghaniensis exuvia

October 6, 2018

Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group, collected an odonate exuvia on 07 June 2018 along either Little Otter Creek or Otter Creek near the place where both creeks are distributaries of Otter Lake in Amherst County, Virginia USA.

A two-step process was used to identify the genus and species of the exuvia.

  1. Determine the family.
  2. Determine the genus and species.

Step 1. Family

First, determine the family of the specimen. For reference, watch the excellent Vimeo video, Identifying dragonfly larva to family (8:06). Here’s the decision tree used to identify the exuvia as a member of the Family Macromiidae (Cruisers).

  • The specimen has a mask-like labium (prementum) that covers the face, as shown in Photo No. 1, characteristic of four families of odonates: Cordulegastridae (Spiketails); Corduliidae (Emeralds); Libellulidae (Skimmers); and Macromiidae (Cruisers).
  • The teeth on the margins of the labium have a regular pattern. (The pattern reminds me of a “spork.”)
  • Its eyes are small, wide set, and stick up.
  • Image No. 2 shows there is a horn on the face-head, characteristic of Macromiidae.

Photo No. 1 shows a face-head view of the exuvia, magnified approximately three times life size (~3x).

No. 1 | Macromia alleghaniensis | exuvia (face-head)

Image No. 2 shows the top of the head of the exuvia, magnified approximately three times life size (~3x). Notice the prominent horn on the face.

No. 2 | Macromia alleghaniensis | exuvia (head-horn)

Step 2. Genus and species

Two dichotomous keys found on p. 27 of Identification Keys to Northeastern Anisoptera Larvae, compiled by Ken Soltesz, were used to determine the genus and species of the exuvia. Markers that match this specimen are highlighted in boldface green text. Three boldface green asterisks (***) are used to highlight the thread for identification of this specimen.

Key to the Genera of the Family Macromiidae

***1b. Lateral spines of abdominal segment 9 do not reach to rearward level of tips of inferior appendages [paraprocts]; Sides of head somewhat convergent behind eyes to pair of low turbercules on hind angles; Lateral setae of labium = 6; Small dorsal hook on segment 10. [Macromia]

A small dorsal hook on abdominal segment 10 is characteristic of Genus Macromia.

No. 3 | Macromia alleghaniensis | exuvia (dorsal-lateral)

Look closely at the full-size version of Image No. 4. Notice the little “nub” on abdominal segment 10 (S10), below the underside of the dorsal hook on abdominal segment nine (S9). The same structure is labeled with a white question mark in Image No. 3.

No. 4 | Macromia alleghaniensis | exuvia (dorsal-lateral)

The lateral spines of abdominal segment 9 (S9) do not reach rearward to the tips of the inferior appendages (paraprocts).

No. 5 | Macromia alleghaniensis | exuvia (dorsal)

Key to the Species of Macromia

1a. Lateral spines of abdominal segments 8 and 9 directed straight to rearward. [illinoiensis]

***1b. Lateral spines of abdominal segments 8 and 9 incurved, especially 8. [alleghaniensis]

The lateral spines of abdominal segments 8 and 9 (S8-9) are incurved, especially segment 8 (S8), indicating this species is alleghaniensis.

No. 6 | Macromia alleghaniensis | exuvia (ventral)

This individual is probably a male, as indicated by what appear to be vestigial hamules located on the ventral side of abdominal segments two and three (S2-3).

Summary

A prominent horn on the face is a key field marker for the Family Macromiidae (Cruisers), a small dorsal hook on abdominal segment 10 is one characteristic of the Genus Macromia, and the lateral spines of abdominal segments 8 and 9 (S8-9) are incurved, indicating the species is alleghaniensis. Therefore this specimen is an Allegheny River Cruiser dragonfly (Macromia alleghaniensis).

Bonus Gallery

No. 7 | Macromia alleghaniensis | exuvia (face-head)

No. 8 | Macromia alleghaniensis | exuvia (dorsal-lateral)

No. 9 | Macromia alleghaniensis | exuvia (dorsal)

Related Resources

Tech Tips

The following equipment was used to shoot Photo/Image No. 3-9: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon EF100mm f/2.8L Macro lens (set for manual focus); Canon MT-26EX-RT Macro Twin Lite set for “Master” mode, and Canon 580 EX- and Canon 580EX II Speedlites set for “Slave” mode. Photo/Image No. 1 and 2Canon MP-E 65mm Macro lens (manual focus only, set for ~3x magnification) plus the multiple-flash setup.

Image No. 2-8 are focus-stacked composite images created and annotated using Adobe Photoshop CC 2017: Image No. 2 (eight photos); Image No. 3 (six photos); Image No. 4 (four photos); Image No. 5 (five photos); Image No. 6 (five photos); Image No. 7 (seven photos); Image No. 8 (seven photos).

Copyright © 2018 Walter Sanford. All rights reserved.


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