Archive for the ‘damselflies’ Category

Denizen of the seep

July 8, 2019

An Ebony Jewelwing damselfly (Calopteryx maculata) was spotted near a forest seep located in Occoquan Regional Park, Fairfax County, Virginia USA. This individual is a male, as indicated by the absence of white pterostigma — a field mark used to identify females of the same species.

Look for Ebony Jewelwing beginning in late-May/early-June along almost any small- to mid-size forest stream in Northern Virginia (USA).

Ebony Jewelwing is a member of Family Calopterygidae (Broad-winged Damselflies). American Rubyspot (Hetaerina americana) is the only other species of Broad-winged Damselfly found in Northern Virginia.

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 C. maculata is from April 27 to October 06. The species is classified as common. Its habitat is “streams, rivers.”

Copyright © 2019 Walter Sanford. All rights reserved.

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Aurora Damsel (mating pair, in heart)

June 14, 2019

The mating pair of Aurora Damsel (Chromagrion conditum) shown in the following photograph is “in wheel,” in which the male uses “claspers” (terminal appendages) at the end of his abdomen to hold the female by her neck/thorax while they are joined at their abdomens. The male — blue, yellow, and black in color — is on top; the female — yellow and black in color — is on the bottom.

The copulatory, or wheel, position is unique to the Odonata, as is the distant separation of the male’s genital opening and copulatory organs. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 377-378). Princeton University Press. Kindle Edition.

The wheel position is sometimes referred to as “in heart” when damselflies mate.

04 JUN 2019 | PNC. William County, VA | Aurora Damsel (mating pair)

Female C. conditum is polymorphic, including two morphs: an andromorph with blue coloration similar to male; or a heteromorph with an entirely yellow thorax, as shown above.

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

Taxonomy

C. conditum is a monotypic genus in the Family Coenagrionidae (Narrow-winged Damselflies).

Copyright © 2019 Walter Sanford. All rights reserved.

Aurora Damsel (male, mating pair)

May 31, 2019

An Aurora Damsel (Chromagrion conditum) was spotted along the shoreline of a small pond located in Prince William County, Virginia USA. Aurora Damsel is a new species for my life list odonates.

This individual is a male, as indicated by his coloration and terminal appendages. Speaking of coloration, notice the underside of the male’s thorax is yellow — a key field mark for Aurora.

21 MAY 2019 | PNC. William County, VA | Aurora Damsel (male)

A mating pair of Aurora Damsel was spotted at the same location. This pair is “in tandem“: the male is on the upper-right; the female on the lower-left.

After copulation, Aurora Damsel engages in a form of guarding behavior known as “contact guarding,” in which the male and female fly “in tandem” to egg-laying sites. Contact guarding is used by most species of damselflies and some species of dragonflies to prevent aggressive males from hijacking the female.

21 MAY 2019 | PNC. William County, VA | Aurora Damsel (mating pair)

Female C. conditum is polymorphic, including two morphs: blue coloration similar to male; or with an entirely yellow thorax, as shown above.

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. The preceding photo is slightly overexposed. As a result, the yellow coloration on both the male and female looks a little washed out.

Credits

Sincere thanks to Gary Myers for the tip that enabled Mike Powell and me to find this uncommon damselfly. See Aurora Damsels in action for Mike’s take on our first time seeing this species.

Copyright © 2019 Walter Sanford. All rights reserved.

Left on the cutting room floor

April 15, 2019

Close readers of my blog may have noticed I’ve posted a lot of photos recently that were taken years ago. Why were the photos passed over for publication closer to the time the shots were taken?

Sometimes there are better shots from the same photowalk that I’m eager to share, and sometimes they just don’t make the grade. The former requires no explanation; the following photos help to illustrate the latter.

The following female Slender Spreadwing damselfly (Lestes rectangularis) was spotted during a photowalk around a vernal pool in the forest at Huntley Meadows Park. The damselfly was perched in a hidey-hole in the vegetation at angle that made it impossible to get the entire subject in focus from head-to-tail.

The first photo shows the head and thorax in focus, but the tip of the abdomen and terminal appendages are out of focus.

15 SEP 2016 | HMP | Slender Spreadwing (female)

The last photo shows the tip of the abdomen and terminal appendages in focus, but the head and thorax are in soft focus. Look closely at a full-size version of the photo and you can see both styli (sing. stylus), structures that serve as sensors (like “curb feelers“) in egg positioning during oviposition.

15 SEP 2016 | HMP | Slender Spreadwing (female)

The odd thing is the focus point is nearly the same in both photos, and the aperture is identical. Go figure! Anyway, less than ideal focus is something that will cause me to reject photos every time. And then there’s that “too hot” blade of grass in the lower-right corner — talk about distracting!

Copyright © 2019 Walter Sanford. All rights reserved.

Powdered Dancer damselflies (males)

April 3, 2019

Two Powdered Dancer damselflies (Argia moesta) were spotted along Popes Head Creek near the town of Clifton, Virginia in Fairfax County USA. The stream is accessible via Chapel Road Park.

22 AUG 2016 | Chapel Road Park | Powdered Dancer (male)

Both individuals are male.

22 AUG 2016 | Chapel Road Park | Powdered Dancer (male)

Credits

Sincere thanks to Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group, for help in verifying my tentative identification of the gender of these specimens. (I wanted to be sure neither individual is a blue morph female.)

Related Resource: Powdered Dancer damselfly (female). [tan morph]

Copyright © 2019 Walter Sanford. All rights reserved.

Odonate calendars: VA Flight Dates

March 31, 2019

Google Calendar was used to synthesize “CHECKLIST OF THE DRAGONFLIES AND DAMSELFLIES OF VIRGINIA, April 2017 update” — Dr. Steve Roble’s excellent datasets for the Commonwealth of Virginia — into two calendars: Dragonflies (VA Flight Dates); and Damselflies (VA Flight Dates).

The Google Calendar default color palettes were used to color-code both calendars: Dragonflies is Graphite; and Damselflies is Birch. Individual events on each calendar are also color-coded by family.

Dragonflies

Here’s the way the dragonflies calendar looks using the Chrome Web browser on my Apple iMac desktop computer. Notice the Graphite colored vertical bar to the left of each event that indicates it belongs to the dragonflies calendar.

And here’s the way the dragonflies calendar looks using the free Google Calendar app on my Apple iPad mini 2.

Every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

New for 2019

An interactive version of both calendars is available online. The dragonflies calendar is shown below.

Regrettably, the color-coding is lost in the online, interactive version of both calendars. That is, unless you print the calendar.

Color-coding is also lost when the calendar is exported as an “.ics” file. That’s the bad news. The good news is the calendar can be edited after it is imported into Google Calendar and it’s easy to edit the entries to color-code them any way you like.

The colors of the rainbow (ROYGBIV) were used to color-code the seven families of dragonflies; the equivalent colors in the Google Calendar default color palette are shown in brackets.

  • R = Family Aeshnidae (Darners) [Tomato]
  • O = Family Cordulegastridae (Spiketails) [Tangerine]
  • G = Family Corduliidae (Emeralds) [Basil]
  • Y = Family Gomphidae (Clubtails) [Banana]
  • B = Family Libellulidae (Skimmers) [Peacock]
  • I = Family Macromiidae (Cruisers) [Blueberry]
  • V = Family Petaluridae (Petaltails) [Grape]

The colors for Emeralds and Clubtails were flip-flopped because it just makes sense the Emeralds should be color-coded green!

Damselflies

Here’s the way the damselflies calendar looks using the free Google Calendar app on my Apple iPad mini 2.

Like the dragonflies calendar, every event features the following information: common name; scientific name; early-date/late-date; abundance; and habitat.

“FSL” was used to color-code the three families of damselflies common to the mid-Atlantic states (USA); the equivalent colors in the Google Calendar default color palette are shown in brackets.

  • F – Family Calopterygidae (Broad-winged Damselflies) [Flamingo (formerly Tomato)]
  • S – Family Coenagrionidae (Narrow-winged Damselflies) [Sage (formerly Peacock)]
  • L – Family Lestidae (Spreadwings) [Lavendar (formerly Basil)]

For what it’s worth, all of the colors for the damselflies calendar are pastel shades.

New for 2019

An interactive version of the damselflies calendars is available online, as shown below.

Dragonflies and Damselflies

The damselflies calendar was updated for 2019 so that no colors are duplicated from the dragonflies calendar. This should help to eliminate confusion when both calendars are displayed at the same time, as shown below.

Lessons Learned

As I worked on the calendar, patterns began to emerge that I hadn’t noticed before. For example, it’s clear that the serious odonate hunter needs to hit the ground running as soon as early March. Remember that Dr. Roble’s dataset is for the entire state. You may not see a given species on its early-date, but it could be seen on that date and certainly can’t be seen if you don’t look!

Tech Tips

Download the “.ics” file from the Virginia Odonata Facebook group. Launch Google Calendar on a desktop computer. Create a new calendar by clicking on the three vertical dots to the right of “Add calendar” and selecting “Create new calendar”; give the calendar a name such as “Test Calendar” and click on the “Create calendar” button. (You can change the name later.) “Test Calendar” should appear in the list of calendars under “My calendars.”

Mouse-over the name “Test Calendar” and click on the vertical column of three dots, labeled “Options for Test Calendar” then select “Settings and sharing.” In the upper-left sidebar, click on “Import and export”; select the “.ics” file to import and select “Test Calendar” from the drop-down menu labeled “Add to calendar.” There are 143 events in the Dragonflies calendar; 56 events in the Damselflies calendar.

If you decide to color-code individual events like I did, click on an event then click on the pencil icon labeled “Edit event.” Select a color and click the “Save” button, then click the radio button for “All events.” Beware: You can right-click on an individual event and change its color but DON’T GO THERE! That results in an event that doesn’t occur annually using the new color you chose.

Related Resources

Kevin Munroe, former manager of Huntley Meadows Park, created an excellent calendar called Dragonflies of Northern Virginia – Flight Periods. This calendar is a valuable resource for hunting dragonflies in Northern Virginia. I think the value of Kevin Munroe’s calendar is enhanced by using it in combination with my visualization of Steve Roble’s dataset.

Dragonflies & Damselflies of Loudoun County features a flight calendar for dragonflies and damselflies.

Copyright © 2019 Walter Sanford. All rights reserved.

Powdered Dancer damselfly (female)

March 29, 2019

A Powdered Dancer damselfly (Argia moesta) was spotted during a photowalk along a small stream at Hemlock Overlook Regional Park, Fairfax County, Virginia USA.

This individual is a female, as indicated by her coloration. Female Powdered Dancers are polymorphic: this is the tan morph; there is also a blue morph that looks somewhat similar to males of the same species.

10 MAY 2017 | HORP | Powdered Dancer (female)

Also notice the female’s abdomen is thicker near the tip than the tip of a male’s abdomen, due to female egg-laying anatomy.

Credits

Sincere thanks to Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group, for help in identifying this specimen. My tentative identification, recorded in field notes dated 10 May 2017, proved to be incorrect.

I’m comfortable identifying some members of two of the three families of damselflies that occur in the mid-Atlantic states (USA), including Family Calopterygidae (Broad-winged Damselflies) and Family Lestidae (Spreadwings). Most members of the Family Coenagrionidae (Narrow-winged Damselflies), not so much.

I remember clearly the time when I was learning to identify dragonflies. I was more than a little confused at first. With persistence, the puzzle pieces started to fall into place sooner than I expected. Same story when I started learning to identify odonate exuviae. Never happened with damselflies, for whatever reason.

Copyright © 2019 Walter Sanford. All rights reserved.

Familiar Bluet damselfly (male)

March 27, 2019

A Familiar Bluet damselfly (Enallagma civile) was spotted during a photowalk at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

This individual is a male, as indicated by the pattern of coloration on his abdomen. Female E. civile is polymorphic, including two morphs: tan; and blue. Female blue morphs have a different pattern of black and blue markings on their abdomen than males of the same species.

21 SEP 2016 | Occoquan Bay NWR | Familiar Bluet (male)

Related Resource: Familiar Bluet damselfly (female).

Credits

Sincere thanks to Mike Boatwright and Michael Moore for verifying my tentative identification of the damselfly. Mike Boatwright is the founder and administrator of the Virginia Odonata Facebook group; Dr. Michael Moore is a professor in the Department of Biological Sciences at University of Delaware and odonate expert extraordinaire. Michael’s new Web site is a treasure trove of helpful resources.

Copyright © 2019 Walter Sanford. All rights reserved.

Blue-fronted Dancers (male, female)

March 22, 2019

Male

A Blue-fronted Dancer damselfly (Argia apicalis) was spotted near Mulligan Pond at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA.

This individual is a male, as indicated by the pattern of blue coloration on his thorax and abdomen, plus the blue coloration on abdominal segments eight through 10 (S8-10).

25 SEP 2016 | Jackson Miles Abbott WR | Blue-fronted Dancer (male)

Female

Several Blue-fronted Dancers were spotted during a photowalk along Accotink Creek/Great Blue Heron Trail at Accotink Bay Wildlife Refuge (ABWR), Fairfax County, Virginia USA.

The first individual is a female, as indicated by two field marks.

Eyes brown, darker above; lack of blue in eyes in andromorph good distinction from male. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 3451-3452). Princeton University Press. Kindle Edition.

Female Blue-fronted Dancers are polymorphicandromorph females are blue like males; heteromorph females are brown-green. Andromorph females tend to be a lighter shade of blue than males of the same species.

This individual is a blue andromorph. Regardless of the color morph…

females never have blue on the last abdominal segments (S8-10). Source Credit: Michael Boatwright, founder and administrator of the Virginia Odonata Facebook group.

02 AUG 2016 | ABWR | Blue-fronted Dancer (female)

More males

Two male Blue-fronted Dancers were spotted at Accotink Bay Wildlife Refuge.

02 AUG 2016 | ABWR | Blue-fronted Dancer (male)

02 AUG 2016 | ABWR | Blue-fronted Dancer (male)

Copyright © 2019 Walter Sanford. All rights reserved.

Top 10 Photos of 2018

January 2, 2019

The following gallery shows 18 finalists for my “Top 10 Photos of 2018.” The photos are presented in reverse-chronological order beginning in September 2018 and ending in February 2018.

No. 1

20 SEP 2018 | Fairfax County, VA | Pandora Sphinx moth

No. 2

23 AUG 2018 | Occoquan Bay NWR | Osprey (male, plus prey)

No. 3

No. 4

No. 5

No. 6

05 JUL 2018 | Fairfax County, VA | Sable Clubtail (female)

No. 7

No. 8

No. 9

12 JUN 2018 | Fairfax County, VA | Sable Clubtail (male)

No. 10

08 JUN 2018 | Fairfax County, VA | Sable Clubtail (male)

No. 11

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

No. 12

No. 13

No. 14

No. 15

No. 16

No. 17

No. 18

Editor’s Note: The following location codes are used in some photo captions, shown above.

Copyright © 2019 Walter Sanford. All rights reserved.


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