Archive for August, 2015

Surprise!

August 11, 2015

Common Sanddragon (Progomphus obscurus) is a member of the Clubtail Family of dragonflies that is spotted during June and July in mid-Atlantic United States like Virginia.

I thought I’d seen the last Common Sanddragons of 2015 in late June. Imagine my surprise when I saw one during the first week in August!

A Common Sanddragon dragonfly (Progomphus obscurus) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Common Sanddragon (male)

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

A Common Sanddragon dragonfly (Progomphus obscurus) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Common Sanddragon (male)

He was perching on a sandy beach, facing the water, in the stream bed of Dogue Creek where it flows through Wickford Park.

A Common Sanddragon dragonfly (Progomphus obscurus) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Common Sanddragon (male)

Notice the blue rock at the lower-right in the following photo. Azurite is a deep blue copper mineral produced by weathered copper ore, although I’m skeptical there are copper deposits located in/near Dogue Creek.

A Common Sanddragon dragonfly (Progomphus obscurus) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Common Sanddragon (male)

Copyright © 2015 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 mark 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.

Vernal Pools are Wet and Dry

August 7, 2015

It’s an honor to announce one of my dragonfly photographs is featured on signage for a man-made vernal pool at Butternut Creek Recreation and Nature Area, a new park in the Town of DeWitt, New York.

The info-graphic, entitled “Vernals Pools are Wet and Dry,” was written by Christine Manchester, Naturalist and Sustainability Coordinator, and illustrated by Kate Woodle.

Vernal-pool-signage_s_0389

05 JUN 2015 | Photo used with permission from Kate Woodle.

The preceding photograph shows the sign located in situ on the day the park opened; the final version of the illustration for the sign is shown below.

Vernal-Pool-Final

Graphic used with permission from the Town of DeWitt.

One of my photos of a Swamp Darner dragonfly (Epiaeschna heros), taken during a photowalk at Huntley Meadows Park (HMP) on 02 June 2014, is featured on the sign. The dragonfly is a female, shown laying eggs (oviposition) in mud alongside a vernal pool.

The original photograph is shown below. Did you notice the version on the sign is the mirror image of my photo? I guess you call that “artistic license.”

Related Resource: An annotated version of the same photo illustrates some of the reproductive anatomy for female Swamp Darners.

Copyright © 2015 Walter Sanford. All rights reserved.

Another male Banded Pennant dragonfly

August 5, 2015

Another male Banded Pennant dragonfly (Celithemis fasciata) was spotted during a photowalk around Mulligan Pond, Jackson Miles Abbott Wetland Refuge.

A Banded Pennant dragonfly (Celithemis fasciata) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Banded Pennant (male)

The following photograph is my favorite in the set.

A Banded Pennant dragonfly (Celithemis fasciata) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Banded Pennant (male)

The last photo breaks at least one rule of composition, yet it seems to work.

A Banded Pennant dragonfly (Celithemis fasciata) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Banded Pennant (male)

Copyright © 2015 Walter Sanford. All rights reserved.

Blue-fronted Dancer damselflies (males)

August 3, 2015

Two Blue-fronted Dancer damselflies (Argia apicalis) were spotted during a photowalk around Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR). Both individuals are males.

A Blue-fronted Dancer damselfly (Argia apicalis) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Blue-fronted Dancer (male)

This is the first time I have seen Blue-fronted Dancers in Virginia, although I have seen them in Maryland along the Little Patuxent River, Patuxent Research Refuge (North Tract).

A Blue-fronted Dancer damselfly (Argia apicalis) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

24 JUL 2015 | JMAWR | Blue-fronted Dancer (male)

Sidebar: Scientific Classification of Damselflies

The following concise explanation of the scientific classification of damselflies is provided to help the reader understand where Blue-fronted Dancers fit into the bigger picture of the Order OdonataSuborder Zygoptera (Damselflies).

There are four 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).

  • Argia (e.g., Blue-fronted Dancer, Blue-tipped Dancer, Variable Dancer)
  • Enallagma (e.g., Big Bluet, Familiar Bluet, Orange Bluet, Stream Bluet)
  • Ischnura (e.g., Eastern Forktail, Fragile Forktail, Rambur’s Forktail)

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!

Editor’s Note: Please comment to let me know whether the preceding information is helpful.

Related Resources:

Copyright © 2015 Walter Sanford. All rights reserved.

Maturation

August 1, 2015

Widow Skimmer dragonfly (Libellula luctuosa) was spotted during a photowalk around Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR).

A Widow Skimmer dragonfly (Libellula luctuosa) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a mature male.

24 JUL 2015 | JMAWR | Widow Skimmer (mature male)

This individual is a mature male that has mated many times, as indicated by his coloration, terminal appendages, and scratches on the abdomen.

Males that have mated often have marks on their abdomen where the female legs have scratched them. This is especially obvious in species in which males develop pruinosity, as the pruinosity on the midabdomen is scratched off, and the signs are visible at some distance. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 390-392). Princeton University Press. Kindle Edition.

A Widow Skimmer dragonfly (Libellula luctuosa) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a mature male.

24 JUL 2015 | JMAWR | Widow Skimmer (mature male)

Contrast the appearance of the mature male Widow Skimmer with the following immature male, spotted at Huntley Meadows Park (HMP). Notice the mature male has two features that differentiate it from the immature male: white wing spots; and white pruinescence covering part of its thorax and all of its abdomen.

A Widow Skimmer dragonfly (Libellula luctuosa) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is an immature male.

06 JUN 2015 | HMP | Widow Skimmer (immature male)

“Maturation,” the title of this post, also refers to my growth as an odonate hunter and photographer/photo editor. One look at the following photographs of the first Widow Skimmer I saw in the field, and it’s evident I’ve progressed to a higher level of dragonfly spotting during the past three years.

The preceding gallery features a male Widow Skimmer spotted at Lake Allen, Patuxent Research Refuge (North Tract). Admittedly not my best work, these photos were taken the first time I used a DSLR camera.

Copyright © 2015 Walter Sanford. All rights reserved.


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