Posts Tagged ‘malformed’

Black-shouldered Spinyleg (female)

July 24, 2018

A Black-shouldered Spinyleg dragonfly (Dromogomphus spinosus) was spotted along an unnamed small creek in Fairfax County, Virginia USA. This individual is a female, as indicated by her terminal appendages.

19 JUl 2018 | Fairfax County, VA | Black-shouldered Spinyleg (female)

The tip of the dragonfly’s right hind wing appears to be slightly malformed; her ability to fly didn’t seem to be impaired by the malformation.

Look at the full-size version of the following photo. Notice the fuzzy schmutz on her face and legs. I speculate the dragonfly might have enjoyed either a butterfly or moth for her last meal.

19 JUl 2018 | Fairfax County, VA | Black-shouldered Spinyleg (female)

Copyright © 2018 Walter Sanford. All rights reserved.

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“Bender” on grass

June 22, 2018

Gray Petaltail dragonfly (Tachopteryx thoreyi) is well-known for its tendency to perch on gray and tan colored surfaces, including tree trunks. Less well-known is the fact that Gray Petaltail perches wherever it wants, including tall grasses growing in the forested seeps from which the species emerges.

“Bender,” my nickname for a male Gray Petaltail with a malformed abdomen, is shown perched on grass stems in the following photo set.

No. 1 | 06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

The next photo provides a good view of the gentle curve in Bender’s abdomen, as well as his hamules, visible on the ventral side of abdominal segments two and three (S2 and S3).

No. 2 | 06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

Like many male odonates, Bender probably perched on the grass in order to make himself available for hook-ups with females of the same species.

No. 3 | 06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

Bender aggressively defended the prominent perch against other odonates that intruded upon his territory.

No. 4 | 06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

No flash/flash

Compare/contrast Photo No. 3-4. The batteries in my external flash unit were almost drained completely by the time I shot the photos. As a result, the flash worked sometimes and didn’t work other times. I’m fairly certain the flash didn’t fire for the Photo No. 3, and equally certain it fired for Photo No. 4. Some photographers might contend the no-flash photo is “arty”; I contend Photo No. 4 — the fill-flash version — has better color balance, color saturation, and more detail in the shadows.

Copyright © 2018 Walter Sanford. All rights reserved.

“Bender” on bark

June 20, 2018

I nicknamed this male Gray Petaltail dragonfly (Tachopteryx thoreyi) “Bender” because of his malformed abdomen.

06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

Bender is shown perched on a tree that fell across a forested seep. It’s possible the tree makes the seep seepier, and that’s a good thing for the Gray Petaltail larvae that are well-adapted for this specific type of habitat.

06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

Just look at that face — Bender exudes personality! In the following photo, Bender perched in a spot so that he was looking at me directly. Yep, that’s when we bonded.

06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

Next post: “Bender” on grass. No, wait — that doesn’t sound right!

Copyright © 2018 Walter Sanford. All rights reserved.

Introducing “Bender”

June 12, 2018

Gray Petaltail dragonfly (Tachopteryx thoreyi) was spotted at a forested seep. This individual is a male, as indicated by his “indented” hind wings and terminal appendages.

06 JUN 2018 | Northern Virginia | Gray Petaltail (male)

I nicknamed this male “Bender” because of his malformed abdomen. Bender is a scrappy fighter who aggressively defended his territory against other odonate intruders!

More photos of Bender will be published in one or more upcoming blog posts.

Copyright © 2018 Walter Sanford. All rights reserved.

Blue Corporal (teneral females)

May 1, 2018

Lots of Blue Corporal dragonflies (Ladona deplanata) were spotted near Painted Turtle Pond at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. This is the first time the author has observed Blue Corporal at Painted Turtle Pond.

Both individuals featured in this post are teneral females, as indicated by their tenuous wings and terminal appendages.

Female 1

The first female was spotted perching on vegetation near the shoreline of Painted Turtle Pond. Some of the ground cover is charred from a recent controlled burn at Occoquan Bay NWR.

The common name for Blue Corporal is derived from two cream-colored stripes that appear on the front of the thorax, similar to the two stripes that signify the rank of corporal in the military.

Notice the abdomen of this female seems to be bent slightly to the right (facing forward). This malformation probably occurred during emergence.

Female 2

The last female was spotted perching on the gravel road leading to Painted Turtle Pond. The purple rock located in the upper-right corner of the photo might contain the mineral fluorite.

Like many teneral dragonflies, if not most, this individual was quite skittish. I followed the female to two locations before calling the photowalk a wrap.

Related Resource: Blue Corporal (teneral males).

Copyright © 2018 Walter Sanford. All rights reserved.

Cobra Clubtail dragonflies (females)

December 6, 2017

Male and female Cobra Clubtail dragonflies (Gomphurus vastus) are nearly identical in appearance except for their terminal appendages: females have two terminal appendages (cerci); males have three (claspers). Also notice the subtle difference in the shape of their hind wings: female hind wings are rounded; male hind wings are “indented.”

Several female Cobra Clubtails were photographed during the annual mass emergence along the Potomac River at Riverbend Park, Fairfax County, Virginia USA.

The first female, shown above, has a malformed wing.

Notice part of an insect leg on the wooden beam, underneath the female’s abdomen. Is it a leftover from a late-morning snack?

Copyright © 2017 Walter Sanford. All rights reserved.

American Rubyspot damselfly (female)

July 27, 2017

An American Rubyspot damselfly (Hetaerina americana) was spotted during a photowalk along Bull Run in Fairfax County, Virginia USA. As far as I know, this is the first official record for American Rubyspot at this location.

This individual is a female, as indicated by her terminal appendages and ovipositor.

21 JUN 2017 | Fairfax County, VA | American Rubyspot (female)

Notice one of the damselfly’s wings is either malformed or injured. She was able to fly, although it seemed to be a struggle.

The Backstory

The damselfly landed on my thigh a few minutes before the preceding photograph was taken. It was like she was pleading with me to help her, although I admit I tend to project my thoughts onto the odonates I photograph. I would have tried to unfold her wing, but I never had an opportunity. Two teenage girls and a bear-sized dog startled me! (I never heard/saw them approaching. The girls told me their dog is a Long Hair German Shepherd.) When I flinched the damselfly flew to the perch shown above, just beyond my reach.

Copyright © 2017 Walter Sanford. All rights reserved.

Common Sanddragon (male)

July 23, 2017

A Common Sanddragon dragonfly (Progomphus obscurus) was spotted along Dogue Creek at Wickford Park, Fairfax County, Virginia USA. This individual is a male, as indicated by his terminal appendages and “indented” hind wings.

Some people imagine the yellow markings along the abdomen look like small burning candles.

All of the photographs in this set are uncropped. Knee-high rubber boots enabled me to photowalk some segments the stream, allowing me to get close to the subject.

This guy was a cooperative model; he allowed me to photograph him from many viewpoints.

The water level was relatively high after recent heavy rainfall. As a result, there were fewer sandy “beaches” than usual along the stream. I speculate the dragonfly may have been more cooperative because he wasn’t going to abandon one of only a few available preferred places to perch.

It’s possible the right front leg (facing forward) is either malformed or injured. Although the male flew several short patrols, landing in different places, the leg was never fully extended.

Copyright © 2017 Walter Sanford. All rights reserved.

Spine-crowned Clubtail (terminal appendages)

May 10, 2017

A male and female Spine-crowned Clubtail dragonfly (Hylogomphus abbreviatus) were spotted recently in Fairfax County, Virginia USA.

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”). The epiproct for Spine-crowned Clubtail is essentially a wide plate with two prongs.

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

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

The hind wings of male clubtail dragonflies are “indented” near the body, as shown in the preceding photograph. In contrast, the hind wings of female clubtails are rounded (shown below). Also notice the right hind wing of the male is slightly malformed.

Female

Female dragonflies have a pair of cerci (superior appendages) that have little or no function. The abdomen of female Spine-crowned Clubtails is noticeably thicker than males of the same species.

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (female)

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

Copyright © 2017 Walter Sanford. All rights reserved.

Spine-crowned Clubtail dragonfly (male)

May 8, 2017

A Spine-crowned Clubtail dragonfly (Hylogomphus abbreviatus) was spotted recently in Fairfax County, Virginia USA. Spine-crowned Clubtail is relatively uncommon in Northern Virginia, and a new species of dragonfly for my life list.

This individual is a male, as indicated by his terminal appendages and indented hind wings. Notice the right hind wing is slightly malformed.

Spine-crowned Clubtail versus Cobra Clubtail

Spined-crowned Clubtail looks similar to Cobra Clubtail (Gomphurus vastus). Two field markers can be used to differentiate the species.

Spine-crowned Clubtail features large yellow spots on the sides of abdominal segments eight and nine (S8-9); Cobra Clubtail has a small yellow spot on the side of abdominal segment eight (S8) and a large yellow spot on the side of abdominal segment nine (S9), as shown below (see inset photo).

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

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

The face of Spine-crowned Clubtail is yellow and unmarked; the face of Cobra Clubtail is yellow with horizontal black markings (see inset photo).

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

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

More photos, Spine-crowned Clubtail

This guy was a cooperative model as I followed him to several perches on rocks along a large stream.

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

03 MAY 2017 | Fairfax County, VA | Spine-crowned Clubtail (male)

Editor’s Notes: Special thanks to Mike Boatwright, curator of the Virginia Odonata Facebook group, for help in verifying my tentative field identification. As far as I know, this is the first official record for Hylogomphus abbreviatus in Fairfax County, Virginia.

Copyright © 2017 Walter Sanford. All rights reserved.


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