Posts Tagged ‘Family Corduliidae (Emeralds)’

Common Baskettail (teneral female)

April 29, 2018

A Common Baskettail dragonfly (Epitheca cynosura) was spotted near Painted Turtle Pond during a photowalk at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

This individual is a teneral female, as indicated by her tenuous wings and relatively short, straight terminal appendages.

Spring 2018 has been slow to spring in the mid-Atlantic USA, as evidenced by the fact that the first Common Baskettails were spotted at Painted Turtle Pond beginning in mid-April 2017.

Related Resources

Copyright © 2018 Walter Sanford. All rights reserved.

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A good spot for spiketails and emeralds

April 23, 2018

21 APR 2017 | Huntley Meadows Park | Little Hunting Creek

The preceding photo shows a view of the forest, seen from the banks of Little Hunting Creek as it flows through Huntley Meadows Park, Fairfax County, Virginia USA. The forest floor is carpeted with Spring Beauty wildflowers (Claytonia virginica).

Little Hunting Creek is a good place to look for Twin-spotted Spiketail dragonflies (Cordulegaster maculata). Arrowhead Spiketail dragonflies (Cordulegaster obliqua) and Mocha Emerald dragonflies (Somatochlora linearis) have been observed at the same site.

Tech Tip: I used my Panasonic Lumix DMC-FZ150 superzoom camera to shoot the landscape photo featured in this blog post. The camera was set for manual focus at the hyperfocal distance for an aperture of f/4, based upon the instructions provided in the excellent video tutorial by Graham Houghton, “Panasonic Lumix FZ camera easier manual focus method — super point-and-shoot tip.”

Copyright © 2018 Walter Sanford. All rights reserved.

New discoveries in 2017 (odonates)

December 28, 2017

There’s always more to discover/learn! My odonate-related new discoveries in 2017 are presented in reverse-chronological order.

Fine-lined Emerald dragonfly

A Fine-lined Emerald dragonfly (Somatochlora filosa) was spotted at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. This individual is one of several males spotted during a period of a week-or-so in mid-September 2017.

Immature male Calico Pennant

20 JUN 2017 | OBNWR | Calico Pennant (immature male)

A Calico Pennant dragonfly (Celithemis elisa) was spotted at Painted Turtle Pond, Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. This individual is an immature male. Notice its coloration is similar to female Calico Pennants.

Allegheny River Cruiser dragonfly

An Allegheny River Cruiser (Macromia alleghaniensis) was netted by Mike Blust at Hardware River Wildlife Management Area, Fluvanna County, Virginia USA. This individual is a male.

Harpoon Clubtail dragonfly

09 JUN 2017 | Highland County, VA | Harpoon Clubtail (male)

A Harpoon Clubtail dragonfly (Phanogomphus descriptus) was spotted at “Straight Fork,” Highland County, Virginia USA. This individual is a male. Sincere thanks to fellow Virginians Karen Kearney and Mike Boatwright for guiding me to this unique high-elevation habitat.

It’s worth noting that I saw two more new species during the same trip: Riffle Snaketail (Ophiogomphus carolus); and Dot-tailed Whiteface (Leucorrhinia intacta).

Those who know me well are familiar with one of many “Walterisms”: “I haven’t ‘seen’ something until I have photographed it.” My rationale is two-fold: 1) A photograph verifies a sighting. 2) The detail visible in a good photograph exceeds the acuity of the human eye. Suffice it to say I saw two other species but haven’t seen them. Makes sense to me!

Swift River Cruiser dragonfly

A Swift River Cruiser dragonfly (Macromia illinoiensis) was spotted at Riverbend Park, Fairfax County, Virginia USA. This individual is an emergent/teneral female.

Spine-crowned Clubtail dragonfly

A Spine-crowned Clubtail dragonfly (Hylogomphus abbreviatus) spotted along Bull Run at Hemlock Overlook Regional Park, Fairfax County, Virginia USA. This individual is a male. A female was spotted on the same day at a nearby location.

Epitheca cynosura exuvia

A Common Baskettail dragonfly (Epitheca cynosura) exuvia was collected at Painted Turtle Pond, Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

Epitheca princeps exuvia

05 MAR 2017 | Prince Baskettail (Epitheca princeps) | exuvia (face-head)

A Prince Baskettail dragonfly (Epitheca princeps) exuvia was collected from an unknown location. This specimen was on temporary loan from Huntley Meadows Park, Fairfax County, Virginia USA.

Copyright © 2017 Walter Sanford. All rights reserved.

Mocha Emerald terminal appendages (female)

September 29, 2017

Mocha Emerald dragonfly (Somatochlora linearis) was spotted by Andrew Rapp in Henrico County, Virginia USA. This individual is a female.

Terminal appendages

All female dragonflies have a pair of cerci (superior appendages) that have little or no function. The hind wings of female Mocha Emerald dragonflies are rounded.

21 JUL 2017 | Henrico County, VA | Mocha Emerald (female)

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

21 JUL 2017 | Henrico County, VA | Mocha Emerald (female)

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

Notice the subgenital plate shown in the preceding photo.

subgenital plate: plate below S8 that holds bunches of eggs when enlarged; variable enough in shape to be of value in identification. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 11723-11724). Princeton University Press. Kindle Edition.

“S8” refers to abdominal segment eight. Remember that all dragonflies and damselflies have a 10-segmented abdomen, numbered from front to back.

Oviposition (egg-laying)

The following Apple iPhone 3GS “raw” video clip shows a female Mocha Emerald dragonfly laying eggs by the process of oviposition. The process typically lasts a few seconds to a few minutes. This individual was spotted on 16 July 2011 during a photowalk through the “Wildlife Sanctuary,” one of seven small parks in the community of Hollin Hills, Fairfax County, Virginia USA.

Mocha Emerald dragonfly (female, ovipositing) [Ver. 2] (0:23)

Related Resource: Mocha Emerald terminal appendages (male).

Editor’s Note: Sincere thanks to Andrew Rapp for permission to use his still photographs.

Copyright © 2017 Walter Sanford. All rights reserved.

Fine-lined Emerald dragonfly redux (Part 2)

September 21, 2017

The same Fine-lined Emerald dragonfly (Somatochlora filosa) was photographed while it perched on grasses located in two shady places along one of the trails at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

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

Set 3

A busy background of thigh-high grasses made it challenging to find a pleasing composition.

Set 4

Photo Set 4 is my favorite, in terms of both quantity and quality. The dragonfly is shown perching on a grass stem that is estimated to be more than six feet high.

The next three photos are uncropped, that is, full-size images (4,000 x 3,000 pixels). This individual has a distinctive eye injury to the top of his left eye (facing forward) that enabled me to recognize the same male dragonfly is the subject in all four photo sets.

Did you notice the male Big Bluet damselfly (Enallagma durum) that photo-bombed the preceding image?

The last photo was cropped lightly in order to improve the composition, and Adobe Photoshop CC 2017 was used to remove a distracting element from the lower-right corner of the image.

Related Resources

Copyright © 2017 Walter Sanford. All rights reserved.

Fine-lined Emerald dragonfly redux (Part 1)

September 19, 2017

Several Fine-lined Emerald dragonflies (Somatochlora filosa) were spotted during a photowalk at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

The same dragonfly was photographed while it perched in several shady places along one of the trails at the park. In my limited experience, Somatochlora filosa seems to prefer perching on bare tree branches or long stems of wild grass. Part 1 features two photo sets showing Fine-lined Emerald resting on other types of perches; Part 2 will feature two more photo sets showing the dragonfly perching on grasses.

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

Set 1

The first photograph is a strong contender for my Odonart Portfolio. I like the way the green vegatation complements the dragonfly’s emerald colored eyes. Can anyone identify the type of plant on which the dragonfly is perching?

Post Update: Sincere thanks to Drew Chaney for identifying the green plant shown in the preceding photo. According to Drew, “It’s common evening-primrose, probably Oenothera biennis.”

Set 2

The second set of photos shows the dragonfly perching on a Common Milkweed (Asclepias syriaca) seed pod.

The next photo was taken a step-or-so closer…

This individual has a distinctive eye injury to the top of his left eye (facing forward).

And after a few side steps, I was able to take a good ventral-lateral shot.

Editor’s Note: Sincere thanks to several members of the Capital Naturalist Facebook group for identifying the species of milkweed plant shown in photo Set 2. “Capital Naturalist” is administered by Alonso Abugattas, Natural Resources Manager, Arlington County Parks, Virginia.

Related Resources

Copyright © 2017 Walter Sanford. All rights reserved.

Fine-lined Emerald dragonflies (males)

September 13, 2017

Three Fine-lined Emerald dragonflies (Somatochlora filosa) were spotted during a long photowalk at Occoquan Bay National Wildlife Refuge. All three individuals are males, as indicated by their terminal appendages and prominent hamules.

If I have seen further it is by standing on the shoulders of giants. Source Credit: Sir Isaac Newton.

Sincere thanks to Jim Waggener, Wildlife Survey Coordinator for The Audubon Society of Northern Virginia, as well as other members of Jim’s survey group for sharing information that enabled me to find this rare to uncommon species of dragonfly. The group has surveyed four sites in Northern Virginia regularly for many years, including Occoquan Bay National Wildlife Refuge.

No. 1

Fine-lined Emerald dragonflies seem to prefer perching on bare tree branches or long stems of wild grass, typically at chest- or head-height although not exclusively. For example, this guy was perched about waist-high on a cluster of fallen tree branches.

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

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

Fine-lined Emerald seems to prefer perching in sun rather than shade, unlike Mocha Emerald (Somatochlora linearis) — another species from the Family Corduliidae (Emeralds) found in Northern Virginia that prefers shady places.

The following ventral-lateral shot shows the lines on the thorax for which this species is named.

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

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

No. 2

The male shown in the next photo is perched on a long grass stem, about chest-high. He posed for two shots, patrolled back-and-forth a few times, and then disappeared.

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

No. 3

The last male was the most cooperative model. The first photo was taken at a distance of approximately six feet.

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

The next photo was taken a step-or-so closer…

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

And after a few side steps, I was able to take a good lateral shot.

10 SEP 2017 | Occoquan Bay NWR | Fine-lined Emerald (male)

The Backstory

This might be one of those stories in which the take-away is “persistence pays dividends.”

I made two trips to Occoquan Bay NWR during Fall 2016 when Fine-lined Emerald was my target species. On 21 September 2016, I spotted one or more dragonflies (species unknown) patrolling the treetops along one of the trails at OBNWR. I didn’t see any signs of Fine-lined Emerald on 25 October 2016, consistent with records for late-date maintained by Kevin Munroe (04 October for Northern Virginia) and Dr. Steven Roble (15 October for the Commonwealth of Virginia).

In retrospect, I realized I started searching too late in the year during 2016 so I started earlier in 2017. My first trip to OBNWR was on 30 August 2017; it turned out to be fruitless. I hit the jackpot on 10 September 2017! Fine-lined Emerald is a new species for my life list of dragonflies.

Rare to Uncommon

A distribution map of official records for Fine-lined Emerald helps to illustrate its classification as a rare to uncommon species of odonate.

Source Credit: Abbott, J.C. 2006-2017. OdonataCentral: An online resource for the distribution and identification of Odonata. Available at http://www.odonatacentral.org. (Accessed: September 14, 2017).

Key: blue dots = Dot Map Project; green dots = Accepted records; yellow dots = Pending records.

Related Resources

Copyright © 2017 Walter Sanford. All rights reserved.

Adios Mochacho!

September 1, 2017

Mocha Emerald dragonfly (Somatochlora linearis) was spotted along a small creek at a remote location in the forest at Huntley Meadows Park. This individual is a male, as indicated by his terminal appendages and hamules.

The Dragonflies of Northern Virginia Calendar of Flight Periods by Kevin Munroe, former manager at Huntley Meadows Park, shows the adult flight period for Mocha Emerald is from the second week in June through mid-September.

In my experience, July is prime time for Mocha Emerald in Fairfax County, Virginia USA. I spotted many Mochas during a visit to the same location during the second week in July. In contrast, the male featured in this post was the only Mocha Emerald spotted during an intense search along the stream. So it may be time to say “Adios Mocha-cho — see you next year!”

Copyright © 2017 Walter Sanford. All rights reserved.

Mocha Emerald dragonfly claspers

July 13, 2017

Mocha Emerald dragonfly (Somatochlora linearis) was spotted along a small creek at a remote location in the forest at Huntley Meadows Park. This individual is a male, as indicated by his terminal appendages and hamules.

All 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”).

09 JUL 2017 | Huntley Meadows Park | Mocha Emerald (male)

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

09 JUL 2017 | Huntley Meadows Park | Mocha Emerald (male)

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

Male dragonfly secondary genitalia, called hamules, are located below abdominal segments two and three (S2 and S3), as shown in the following annotated image. Hamules come in a variety of sizes and shapes, but their function is identical for all species of odonates.

hamules: paired structures that project from genital pocket under second segment and hold female abdomen in place during copulation Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 11618-116198). Princeton University Press. Kindle Edition.

09 JUL 2017 | Huntley Meadows Park | Mocha Emerald (male)

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

Related Resource: Mocha Emerald terminal appendages (female).

Technique Hint: Did you notice that the “focus” of each photo (not to be confused with the focus point) is shown against a lighter background? That’s no accident — I composed each shot that way. As a result, the terminal appendages (cerci and epiproct) are much easier to see in the first two photos than the last shot, in which the composition highlights the hamules.

Copyright © 2017 Walter Sanford. All rights reserved.

Ashy Clubtail dragonfly (male)

May 20, 2017

An Ashy Clubtail (Phanogomphus lividus) was spotted during a photowalk along a mid-size stream in Fairfax County, Virginia USA.

03 MAY 2017 | Fairfax County, VA | Ashy Clubtail (male)

This individual is a male, as indicated by his terminal appendages and indented hind wings.

03 MAY 2017 | Fairfax County, VA | Ashy Clubtail (male)

The last photo is uncropped. The wider view shows the Ashy Clubtail is well-camouflaged when perching on the ground.

03 MAY 2017 | Fairfax County, VA | Ashy Clubtail (male)

The Backstory

I visited a new location in Fairfax County, Virginia on 03 May 2017, following my hunch that the spot might be a good place to find some of the more uncommon species of odonates. Turns out my hunch was right!

I saw species from four families of dragonflies: male Stream Cruiser dragonfly (Didymops transversa); male Springtime Darner dragonfly (Basiaeschna janata); female and male Common Baskettail dragonfly (Epitheca cynosura); female and male Spine-crowned Clubtail dragonfly (Hylogomphus abbreviatus); at least two male Lancet Clubtail dragonflies (Phanogomphus exilis); and the male Ashy Clubtail (Phanogomphus lividus) featured in this post.

In addition, I saw lots of teneral damselflies from the Family Coenagrionidae (Pond Damsels), possibly Blue-tipped Dancer (Argia tibialis).

03 MAY 2017 | Fairfax County, VA | teneral damselfly

Copyright © 2017 Walter Sanford. All rights reserved.


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