Posts Tagged ‘in heart’

More Big Bluet damselflies

December 24, 2016

More Big Bluet damselflies (Enallagma durum) were spotted in July 2016 during two photowalks along the Potomac River at Dyke Marsh Wildlife Preserve (DMWP).

More males

These individuals are males, as indicated by their blue and black coloration and by their terminal appendages.

Mating pair

The mating pair of Big Bluet damselflies 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 and black in color, is on top; the female, green 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. In this case, the heart shape is deformed slightly.

A mating pair of Big Bluet damselflies (Enallagma durum) spotted at Dyke Marsh Wildlife Preserve, Fairfax County, Virginia USA. This pair is "in heart."

19 JUL 2016 | DMWP | Big Bluet (mating pair, “in tandem”)

The same pair is “in tandem” a while later: the male is on the right; the female is on the left. The male is engaged in “contact guarding,” in which the male and female fly “in tandem” to egg-laying sites. Contact guarding is used by some species of odonates to prevent aggressive males from hijacking the female.

A mating pair of Big Bluet damselflies (Enallagma durum) spotted at Dyke Marsh Wildlife Preserve, Fairfax County, Virginia USA. This pair is "in tandem."

19 JUL 2016 | DMWP | Big Bluet (mating pair, “in tandem”)

Look closely at the underside of the female’s abdomen, near the tip. Notice the ovipositor that she uses 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.

Sidebar: Scientific Classification of Damselflies

The following concise explanation of the scientific classification of damselflies is provided to help the reader understand where the genus Enallagma (American Bluets) fits into the bigger picture of the Order OdonataSuborder Zygoptera (Damselflies).

There are five families of damselflies in the United States of America, although only three families occur in the mid-Atlantic USA: Broad-winged damselflies; Narrow-winged damselflies (a.k.a., Pond Damselflies); and Spreadwing damselflies.

Family Calopterygidae is comprised of two genera.

Family Coenagrionidae is comprised of 14 genera. Three genera are common in Northern Virginia: Argia (Dancers); Enallagma (American Bluets); and Ischnura (Forktails).

Family Lestidae is comprised of two genera.

  • Archilestes (e.g., Great Spreadwing)
  • Lestes (e.g., Slender Spreadwing, Southern Spreadwing, Swamp Spreadwing)

There are relatively few genera of Broad-winged Damselflies and Spreadwing Damselflies. In contrast, there are many more genera and species of Narrow-winged Damselflies — more species, including many that look similar, makes this family the most challenging to learn!

Related Resources: Excellent digital scans created by Gayle and Jeanelle Strickland. Click on the button labeled “Download file” in order to view full-size version of the graphics.

  • Enallagma durum male #4 | male | JPG
  • Enallagma durum female #2 | female | JPG

Copyright © 2016 Walter Sanford. All rights reserved.

Variable Dancer (mating pair, “in heart”)

November 23, 2016

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) was spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR). This pair is “in heart“: the male is on the upper-left; the female on the lower-right.

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This pair is "in heart."

14 JUN 2016 | JMAWR | Variable Dancer (mating pair, “in heart“)

In the following photo, the male is on top; the female on the bottom.

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This pair is "in heart."

14 JUN 2016 | JMAWR | Variable Dancer (mating pair, “in heart“)

The taxonomic classification of Variable Dancer is as follows: Order Odonata (Dragonflies and Damselflies); Suborder Zygoptera (Damselflies); Family Coenagrionidae (Narrow-winged Damselflies); Genus Argia (Dancers); Subspecies Argia fumipennis violacea (Violet Dancer).

Variable Dancer is a habitat generalist that can be found almost anywhere there is water. Mature males are easy to recognize due to their unique coloration — there are no other species of violet damselflies found in the eastern one-third of the United States. Female Variable Dancers, like many female odonates, are more challenging to identify than males.

It’s helpful to get shots of mating pairs of damselflies, especially “in tandem,” since males and females of the same species can look quite different. The excellent high-resolution digital scans by Gayle and Jeanelle Strickland, listed under “Related Resources” (below), provide clear views of male and female Variable Dancer damselflies.

Related Resources: High-resolution digital scans created by Gayle and Jeanelle Strickland.

Copyright © 2016 Walter Sanford. All rights reserved.

Slender Bluet damselflies (mating pair)

October 24, 2016

A mating pair of Slender Bluet damselflies (Enallagma traviatum) was spotted during a photowalk around Mulligan Pond at Jackson Miles Abbott Wetland Refuge (JMAWR). This pair is “in heart“: the male is on top; the female is on the bottom.

A mating pair of Slender Bluet damselflies (Enallagma traviatum) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This pair is "in heart."

14 JUN 2016 | JMAWR | Slender Bluet (mating pair, “in heart”)

This mating pair is my first confirmed sighting of Slender Bluet damselfly. Enallagma traviatum is classified as a member of Family Coenagrionidae (Narrow-winged Damselflies). The Genus Enallagma (American Bluets) is one of three genera in the Family Coenagrionidae that are common in Northern Virginia.

Notice the large postocular spots spots separated by a straight line that look like a dumbbell. The spots are darker blue for males; lighter blue for females. This pattern of post ocular spots may be used to differentiate Slender Bluet from the somewhat similar looking Blue-fronted Dancer damselflies (Argia apicalis): the eye spots are smaller and the straight line is missing for Blue-fronted Dancer.

It’s helpful to get shots of mating pairs of damselflies, especially “in tandem,” since males and females of the same species can look quite different. The excellent high-resolution digital scans by Gayle and Jeanelle Strickland, listed under “Related Resources” (below), provide clear views of male and female Slender Bluet damselflies.

Related Resources:

Copyright © 2016 Walter Sanford. All rights reserved.

Powdered Dancer damselflies (mating pairs)

September 10, 2016

Two mating pairs of Powdered Dancer damselflies (Argia moesta) were spotted during a photowalk along Pope’s Head Creek at Chapel Road Park, Fairfax County, Virginia USA.

The first mating pair is “in heart“: the male is on top; the female is on the bottom.

A mating pair of Powdered Dancer damselflies (Argia moesta) spotted along Pope's Head Creek at Chapel Road Park, Fairfax County, Virginia USA. This pair is "in heart."

29 AUG 2016 | Chapel Road Park | Powdered Dancer (mating pair)

Female Powdered Dancers are polymorphic; the female in the preceding mating pair is the blue morph that looks somewhat similar to males of the same species.

The last mating pair of Powdered Dancers was spotted “in tandem“: the male is on the upper-left; the female is on the lower-right. The female in the following mating pair is the tan morph.

A mating pair of Powdered Dancer damselflies (Argia moesta) spotted along Pope's Head Creek at Chapel Road Park, Fairfax County, Virginia USA. This pair is "in tandem."

29 AUG 2016 | Chapel Road Park | Powdered Dancer (mating pair)

Copyright © 2016 Walter Sanford. All rights reserved.

Slender Spreadwing damselflies (mating pair)

July 30, 2016

The Backstory: A cohort of emergent/teneral Slender Spreadwing damselflies (Lestes rectangularis) was discovered during late-May and early-June 2016 at a vernal pool located in Huntley Meadows Park (HMP). I have seen/photographed many female Slender Spreadwings in the past, but only one male. For the next few weeks, I focused upon finding and photographing mostly males from the cohort.

Mating Pair

A mating pair of Slender Spreadwing damselflies was spotted in a meadow located near a vernal pool from which the pair probably emerged. This pair is “in heart.”

A mating pair of Slender Spreadwing damselflies (Lestes rectangularis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in heart."

24 JUN 2016 | HMP | Slender Spreadwing (mating pair, “in heart“)

All dragonflies and damselflies have a 10-segmented abdomen, numbered from front to back: male damselfly secondary genitalia, called hamules, are located in segments two and three (S2 and S3); female genitalia in segment eight (S8). Damselflies form the mating wheel (also known as the mating heart) in order for their genitalia to connect during copulation.

A mating pair of Slender Spreadwing damselflies (Lestes rectangularis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in heart."

24 JUN 2016 | HMP | Slender Spreadwing (mating pair, “in heart“)

Therefore, the male is on upper-left; the female is on the lower-right.

A mating pair of Slender Spreadwing damselflies (Lestes rectangularis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in heart."

24 JUN 2016 | HMP | Slender Spreadwing (mating pair, “in heart“)

The next photo shows the mating pair “in tandem,” immediately after copulation. Editor’s Note: Male (soft focus); female (sharp focus).

A mating pair of Slender Spreadwing damselflies (Lestes rectangularis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in tandem," after copulation. Note: male (soft focus); female (sharp focus).

24 JUN 2016 | HMP | Slender Spreadwing (mating pair, “in tandem“)

The last photo shows the mating pair, separated after being “in tandem.” The pair decoupled soon after the heart was broken. Editor’s Note: Male (sharp focus); female (soft focus).

A mating pair of Slender Spreadwing damselflies (Lestes rectangularis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair just separated after being "in tandem."

24 JUN 2016 | HMP | Slender Spreadwing (mating pair, after separation)

Editor’s Note: This is Part 1 in a five-part series of blog posts documenting a cohort of Slender Spreadwing damselflies that emerged from a single vernal pool at Huntley Meadows Park, presented in reverse-chronological order from mature, reproducing adults to emergent tenerals.

Copyright © 2016 Walter Sanford. All rights reserved.

Ebony Jewelwing damselflies (male, female)

August 9, 2015

Ebony Jewelwing (Calopteryx maculata) is a member of the Family Calopterygidae (Broad-winged damselflies). They are common from May to July along wooded slow-moving streams such as Dogue Creek in Wickford Park.

Male

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”).

An Ebony Jewelwing damselfly (Calopteryx maculata) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Ebony Jewelwing (male)

The preceding image also shows the male hamules, …

paired structures that project from pocket under the second segment [S2] and hold female abdomen in place during copulationSource Credit: Glossary [of] Some Dragonfly Terms, by Dennis R. Paulson.

After a male damselfly grabs a female with his claspers, he transfers sperm from the genital opening under the ninth abdominal segment (S9) to his hamules, located beneath the second abdominal segment (S2). Next the pair forms the mating wheel, then the male transfers sperm from his hamules to the female through her genital pore under the eighth abdominal segment (S8).

A mating pair of Ebony Jewelwing damselflies (Calopteryx maculata) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is in wheel (in heart).

06 JUN 2015 | HMP | Ebony Jewelwing (mating pair, in wheel)

The copulatory, or wheel, position is unique to the Odonata, as is the distant separation of the male’s genital opening and copulatory organs. That the position looks as much like a heart as a wheel has been noted. 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.

Female A simple field marker may be used to differentiate male and female Ebony Jewelwings: females feature white pterostigmata (see below); males don’t.

An Ebony Jewelwing damselfly (Calopteryx maculata) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is an adult female.

05 AUG 2015 | Wickford Park | Ebony Jewelwing (adult female)

The preceding annotated image illustrates some of the reproductive anatomy of a female Ebony Jewelwing: a cercus (pl. cerci), one of two superior appendages that have little or no function; a stylus (pl. styli), one of two structures that serve as sensors in egg positioning; and an ovipositor that is used to insert eggs into submerged vegetation (endophytic oviposition). Notice the mud on the tip of the female’s abdomen, indicating she laid eggs recently.

Copyright © 2015 Walter Sanford. All rights reserved.

A Southern Fortnight, Part 1 – Year-long mystery solved!

May 5, 2015

The Backstory: A Southern Fortnight

For the first two weeks during May 2015, Southern Spreadwing damselflies (Lestes australis) were observed at a vernal pool and nearby drainage ditch in the forest at Huntley Meadows Park. I spotted approximately six males and several females during the fortnight. Their sudden disappearance seemed to coincide with a population explosion of Eastern Pondhawk dragonflies (Erythemis simplicicollis) in mid-May. Eastern Pondhawks, especially females, are voracious predators with a penchant for preying upon damselflies.


During late-May 2014, I photographed a spreadwing damselfly near a vernal pool at Huntley Meadows Park. When I revisited the photos months later, I realized the damselfly was a species I’d never seen.

Ed Lam, author and illustrator of Damselflies of the Northeast, identified the specimen as either a Southern Spreadwing damselfly (Lestes australis) or Sweetflag Spreadwing damselfly (Lestes forcipatus). According to Ed, this individual “… is a male. Male Southern and Sweetflag cannot be separated in the field.”

That was November 2014. This is May 2015 and they’re back! Although male Southern Spreadwing and Sweetflag Spreadwing damselflies are virtually indistinguishable unless examined in-hand under magnification, I was fortunate to photograph a mating pair. With Ed’s help, we were able to reverse-engineer a positive identification based upon a single key field marker for the female member of the pair: Its ovipositor is too small to be a female Sweetflag, so by the process of elimination these damselflies must be Southern Spreadwing — a new species for both Huntley Meadows Park (HMP) and Fairfax County, Virginia!

A mating pair of Southern Spreadwing damselflies (Lestes australis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is in tandem.

03 MAY 2015 | HMP | Southern Spreadwing (mating pair, in tandem)

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

A mating pair of Southern Spreadwing damselflies (Lestes australis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is in wheel.

03 MAY 2015 | HMP | Southern Spreadwing (mating pair, in wheel)

The final photo in the time-series shows the male member of the mating pair immediately after the male and female separated.

A Southern Spreadwing damselfly (Lestes australis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This is the male member of a mating pair.

03 MAY 2015 | HMP | Southern Spreadwing (male member, mating pair)

The following photos show two slightly different views of another male spreadwing damselfly spotted at the same location as the mating pair. Although it’s possible these damselflies may be Sweetflag Spreadwing, they are probably Southern Spreadwing.

A Southern Spreadwing damselfly (Lestes australis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male.

03 MAY 2015 | Huntley Meadows Park | Southern Spreadwing (male)

A Southern Spreadwing damselfly (Lestes australis) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male.

03 MAY 2015 | Huntley Meadows Park | Southern Spreadwing (male)

Related Resources:

Copyright © 2015 Walter Sanford. All rights reserved.

I heart you!

August 16, 2014

I was looking for mating pairs of Eastern Pondhawk dragonflies (Erythemis simplicicollis) during a photowalk at Huntley Meadows Park on 10 August 2014. Meanwhile my friend Mark Jette spotted a mating pair of damselflies.

The Orange Bluet damselflies (Enallagma signatum) shown in the following photographs are “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, orange and black in color, is on top; the female, green 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.

Orange Bluet damselflies (mating pair, in wheel)

The preceding photograph was edited to highlight the heart shape formed by the mating pair of damselflies.

Orange Bluet damselflies (mating pair, in wheel)

The classic heart shape became deformed as time passed.

Orange Bluet damselflies (mating pair, in wheel)

In case you’re wondering, I spotted four- to five pairs of mating Eastern Pondhawk dragonflies but wasn’t fast enough to shoot a single photograph! Eastern Pondhawks mate quickly, often for just a few seconds and sometimes entirely in mid-air. Usually by the time you spot a mating pair and reach for your camera, the peep show is over: the pair separates when copulation is complete and the female starts laying eggs (oviposition) while the male hover-guards the female from other aggressive males.

Related Resources:

Copyright © 2014 Walter Sanford. All rights reserved.


%d bloggers like this: