Archive for the ‘damselflies’ Category

Big Bluet damselfly (mating pairs)

September 3, 2017

Hundreds, if not thousands, of Big Bluet damselflies (Enallagma durum) were spotted on 30 August 2017 during a photowalk along Deephole Point Road at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

A mating pair of Big Bluet was spotted “in heart.” The male is on the upper-right; the female on the lower-left.

30 AUG 2017 | OBNWR | Big Bluet (mating pair, “in heart“)

Big Bluet females are polymorphic, including a blue morph and brown morph. The female in this mating pair is a blue andromorph.

30 AUG 2017 | OBNWR | Big Bluet (mating pair, “in heart“)

I photographed the following male because he was perching at the right height for me to take the shot while standing. I took one photo before he flew to another perch, closer to the ground.

30 AUG 2017 | OBNWR | Big Bluet (male)

As it turns out, the single male led me to another mating pair of Big Bluet that I hadn’t noticed!

30 AUG 2017 | OBNWR | Big Bluet (mating pair, “in heart“)

The female in the preceding mating pair is a brown heteromorph. Color is a highly variable field marker, and describing color is subjective. In my experience, the heteromorph female Big Bluets native to Northern Virginia are light tan to light olive drab in color.

Copyright © 2017 Walter Sanford. All rights reserved.

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Powdered Dancer (males, female)

August 20, 2017

A Powdered Dancer damselfly (Argia moesta) was spotted during a photowalk along a mid-size rocky stream in Fairfax County, Virginia USA. This individual is a male, as indicated by his terminal appendages. There is a whitish-blue morph female Powdered Dancer, therefore the male’s whitish-blue coloration is insufficient to identify its gender.

21 JUN 2017 | Fairfax County, VA | Powdered Dancer (male)

A week later, a mating pair of Powdered Dancers was spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This pair is “in tandem“: the male is on the upper-left; the female on the lower-right.

28 JUN 2017 | Riverbend Park | Powdered Dancers (mating pair, in tandem)

The male is “contact guarding” the female as the pair flies “in tandem” to egg-laying sites where the female uses her ovipositor to insert eggs into vegetation (endophytic oviposition).

It’s helpful to take photos of mating pairs of damselflies, especially “in tandem,” since males and females of the same species can look quite different.

Female Powdered Dancers are polymorphic, including a whitish-blue andromorph and a brown heteromorph. The brown morph, shown in this pair, is more common than whitish-blue.

28 JUN 2017 | Riverbend Park | Powdered Dancers (mating pair, in tandem)

Did you notice the male Stream Bluet damselfly (Enallagma exsulans) perching near the Powdered Dancers? Thanks to Karen Kearney and Michael Boatwright, members of the Virginia Odonata Facebook group, for confirming my tentative identification of the Stream Bluet.

Copyright © 2017 Walter Sanford. All rights reserved.

Blue-fronted Dancer (male, female)

August 18, 2017

Many Blue-fronted Dancer damselflies (Argia apicalis) were spotted along Bull Run, Hemlock Overlook Regional Park, Fairfax County, Virginia USA.

Male

The first individual is a male, as indicated by his terminal appendages.

21 JUN 2017 | Fairfax County, VA | Blue-fronted Dancer (male)

There is a blue morph female Blue-fronted Dancer, therefore the male’s blue coloration is insufficient to identify its gender.

21 JUN 2017 | Fairfax County, VA | Blue-fronted Dancer (male)

Female

Female Blue-fronted Dancers are polymorphic, including a blue andromorph and a brown heteromorph, shown below. Thanks to Ken Larsen, member of the Virginia Odonata Facebook group, for help in identifying this individual.

21 JUN 2017 | Fairfax County, VA | Blue-fronted Dancer (heteromorph female)

Related Resources:

Copyright © 2017 Walter Sanford. All rights reserved.

Banded Pennant dragonflies (males)

August 12, 2017

Several Banded Pennant dragonflies (Celithemis fasciata) were spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR), Fairfax County, Virginia USA. All of the individuals in this gallery are male, as indicated by their terminal appendages.

Fujifilm X-T1

The first photo was taken using my Fujifilm X-T1 digital camera, Fujinon XF55-200mm zoom lens plus a Fujifilm 11mm extension tube, and Fujifilm EF-X500 shoe mount flash. The lens was set for a focal length of 200mm (~350mm, 35mm equivalent).

The camera was set for an aperture of f/11. I forgot to decrease the aperture to f/16 (one of the lessons learned from recent field testing). Although depth of field (DoF) wasn’t an issue for the lateral view of a male Swift Setwing dragonfly featured in my last post, DoF is an issue for this viewpoint of a male Banded Pennant dragonfly. Notice the head and thorax are in focus; the terminal appendages are not.

02 AUG 2017 | JMAWR | Banded Pennant (male)

Panasonic Lumix DMC-FZ150

The photos in the last set were taken using my Panasonic DMC-FZ150 superzoom bridge camera plus Canon 580EX Speedlite, my go-to kit for photowalking.

02 AUG 2017 | JMAWR | Banded Pennant (male)

Is that a head-tilt I see below? Did you notice the male Variable Dancer damselfly (Argia fumipennis) in the background?

02 AUG 2017 | JMAWR | Banded Pennant (male)

Editor’s Notes

What are the take-aways from looking at photo sets of the same subject taken using different camera kits, shown head-to-head?

First, the Fujifilm X-T1 is a good camera that I should use more often. My comfort level with the Fujifilm camera isn’t the same as my trusty Panasonic, but that should develop in time.

Second, the Panasonic Lumix DMC-FZ150 is capable of capturing high-quality photographs, especially when used in combination with a good external flash unit such as the Canon 580EX Speedlite.

Copyright © 2017 Walter Sanford. All rights reserved.

Dragonhunters

August 4, 2017

Several male Dragonhunter dragonflies (Hagenius brevistylus) were spotted during photowalks along a mid-size rocky stream in Fairfax County, Virginia USA.

I think the first photo looks and feels like summer.

21 JUN 2017 | Fairfax County, VA | Dragonhunter (male)

The next photo is my favorite in the set. Did you notice the male Blue-fronted Dancer damselfly (Argia apicalis) in the background?

21 JUN 2017 | Fairfax County, VA | Dragonhunter (male)

I flushed the last Dragonhunter as I was walking along a path that leads to/from the stream. He flew to a perch on a tree limb overhead, posed for one photo, and flew toward the top of a nearby tree.

26 JUN 2017 | Fairfax County, VA | Dragonhunter (male)

The Backstory

Winter is the longest season, that is, for odonate hunters. OK, I realize winter is three months like every other season, but it certainly seems longer! Winter is a good time for reflecting upon the last ode-hunting season and planning for the next one.

Last winter, I was thinking about new places to explore where I might see Dragonhunter dragonflies. Kevin Munroe, former manager at Huntley Meadows Park, told me about a hotspot for Dragonhunters along Bull Run in Manassas, Virginia. Manassas is a little farther from home than I am willing to travel, especially in heavy traffic. So I used Google Maps (satellite view) to work downstream from Manassas Battlefield Park until I found a location that seemed to have potential.

I had a hunch the new spot would be ideal habitat for Dragonhunters and other less common species of odonates. Turns out my hunch was right! In fact, I considered calling this post “Dragonhunchers” but decided to play it straight.

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.

Pop quiz answer key

June 9, 2017

Perhaps the simplest way to provide answers to the recent pop quiz — in which readers were challenged to identify the gender of two Southern Spreadwing damselflies (Lestes australis) — is to show what the teneral/immature male (shown in my last post) will look like when he’s a little older.

The following photos show Southern Spreadwings spotted at Mason Neck West Park, Fairfax County, Virginia USA. Both individuals are male, as indicated by their terminal appendages and blue coloration.

Both photographs of the male Southern Spreadwings were taken at an angle that shows their terminal appendages clearly.

All male damselflies have four terminal appendages, collectively called “claspers.” Male damselfly terminal appendages don’t look exactly the same for all species of damselflies, but their function is identical. Claspers are used to grab and hold female damselflies during mating: an upper pair of cerci (“superior appendages”) and a lower pair of paraprocts (“inferior appendages”).

In contrast, female damselflies have two cerci (sing. cercus), superior appendages that have little or no function. Notice the two “nubs” at the tip of the abdomen, as shown in the photo of the female Southern Spreadwing that was featured in the pop quiz.

Editor’s Notes: There are five families of damselflies (Suborder Zygoptera) in the United States of America, although only three families occur in the mid-Atlantic region: Family Calopterygidae (Broad-winged Damselflies)Family Coenagrionidae (Narrow-winged Damselflies); and Family Lestidae (Spreadwings).

Male Broad-winged Damselflies and Spreadwing Damselflies have terminal appendages that are large enough to see with the unaided eye. Generally speaking, both male and female Narrow-winged Damselflies are too small to see their terminal appendages clearly in most photographs.

Copyright © 2017 Walter Sanford. All rights reserved.

Pop quiz

June 7, 2017

OK, it’s time to assess what you’ve learned about damselflies by following my blog.

Two Southern Spreadwing damselflies (Lestes australis) were photographed on the same day at the same location. Both damselflies are teneral/immature, that is, they are relatively young. One is a female; one is a male. Can you identify the gender of the damselflies shown in the following photos?

I’ll give you a hint: Examine their terminal appendages by looking at the full-size version of both photos.

No. 1

No. 2

Editor’s Note: The answer key will be published in my next post.

Copyright © 2017 Walter Sanford. All rights reserved.

Voltinism, revisited

April 30, 2017

Voltinism is a term used in biology to indicate the number of broods or generations of an organism in a year. Source Credit: Wikipedia.

Some species of odonates, such as Southern Spreadwing damselfly (Lestes australis), can be multivoltine.

Huntley Meadows Park

Long-term monitoring of a vernal pool at Huntley Meadows Park has shown Southern Spreadwing is multivoltine at that site.

Mason Neck West Park

Males and females from a single brood of Southern Spreadwing were observed during Fall 2016 at Mason Neck West Park; males from another brood were spotted at the same location on 05 April 2017 and again on 18 April 2017. This evidence suggests Southern Spreadwing is multivoltine at Mason Neck West Park (MNWP). Further field observations are necessary to determine whether more than two broods occur at this location.

This individual is a male, as indicated by his coloration and terminal appendages.

Please look at the full-size versions of the preceding photos in order to appreciate the “fresh” coloration that seems to be a noticeable characteristic for many species of recently-emerged odonates.

Copyright © 2017 Walter Sanford. All rights reserved.

Slender Spreadwing damselflies (females)

March 25, 2017

Two female Slender Spreadwing damselflies (Lestes rectangularis) were spotted during a photowalk around a vernal pool in the forest at Huntley Meadows Park.

No. 1

No. 2

Notice the second individual is bluer in color. Coloration is variable, so it’s better to look at other field markers when making an identification.

Copyright © 2017 Walter Sanford. All rights reserved.


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