Posts Tagged ‘habitat specialist’

Hunting spiketail dragonflies in Virginia

January 11, 2022

There are three genera in Family Cordulegastridae (Spiketails) worldwide: Anotogaster; Cordulegaster; and Neallogaster. Only Genus Cordulegaster is found in the United States of America.

Four species of Cordulegaster are found in the Commonwealth of Virginia: Brown Spiketail (C. bilineata); Tiger Spiketail (C. erronea); Twin-spotted Spiketail (C. maculata); and Arrowhead Spiketail (C. obliqua).

It’s all about habitat, habitat, habitat.

In the world of odonates, there are habitat generalists and habitat specialists. Spiketail dragonflies are habitat specialists.

Dennis Paulson’s description of the habitat for each species of spiketail found in Virginia is shown in the following list. Notice the list is generic, meaning, specific names are not given. As you read the descriptions, look for commonalities among the habitats.

1. Cordulegaster sp.

Habitat: Small to midsized rocky streams with good current and muddy pools, typically in forest. Occasionally seen patrolling on larger rivers. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7058-7059). Princeton University Press. Kindle Edition.

2. Cordulegaster sp.

Habitat: Small woodland streams. Source Credit: Paulson, Dennis. Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Location 7145). Princeton University Press. Kindle Edition.

3. Cordulegaster sp.

Habitat: Small swift streams and soft-bottomed muddy seeps in forest, also streams reduced to series of small pools during drier weather. As in some other spiketails, skunk cabbage often present. Source Credit: Paulson, Dennis. Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7081-7082). Princeton University Press. Kindle Edition.

4. Cordulegaster sp.

Habitat: Small forest streams and seeps, often with skunk cabbage and interrupted fern. Source Credit: Paulson, Dennis. Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 7028-7029). Princeton University Press. Kindle Edition.

Commonalities

Did you notice the habitats for all four species of spiketails found in Virginia have two characteristics in common?

  • small streams, sometimes seep-fed
  • located in the forest/woodlands

When we say small streams, we mean smallmuch smaller than you might think! Although Twin-spotted Spiketail can be found along mid-size streams (often near the confluence of a smaller stream with a mid-size stream) we think Twin-spotted are more common on small streams.

Answer Key

The following list shows the species of spiketail that matches each of Dennis Paulson’s habitat descriptions.

  1. Twin-spotted Spiketail (Cordulegaster maculata)
  2. Brown Spiketail (Cordulegaster bilineata)
  3. Arrowhead Spiketail (Cordulegaster obliqua)
  4. Tiger Spiketail (Cordulegaster erronea)

The common name for each species is hyperlinked to a page in Walter Sanford’s Photoblog featuring many photographs of that species. The scientific name for each species is linked to Mike Boatwright’s “Spiketails” gallery of photographs on Facebook; click on each photo to see the identity of the spiketail species.

The spiketail species in the preceding lists are shown in chronological order of emergence in Virginia, with Twin-spotted being the earliest and Tiger being the latest. There is some overlap of adult flight periods for some species. Online, interactive Odonate Calendars help you know when to be on the lookout for each species.

I found a small woodland stream. Where should I look for spiketails?

If you’re planning to hunt for spiketails during the 2022 odonate season, the time is now to start scouting small streams in the forest such as the one shown in the following photo.

Photo used with written permission from Mike Boatwright.

Our advice: Focus on finding the right habitat first, rather than finding a particular species of spiketail. Revisit the same small stream(s) periodically throughout the entire odonate season to see which species prefer the stream(s). Be peristent — persistence pays when hunting spiketails!

Twin-spotted Spiketail and Brown Spiketail can be found perching either in fields or along trails located near the small streams from which they emerge. In our experience, Brown Spiketail spends the most time perching of all species of spiketails found in Virginia.

Arrowhead Spiketail and Tiger Spiketail fly long patrols back-and-forth along the stream channel itself, approximately six inches (6″) above the water level. Arrowhead Spiketail stops to perch at the end points of its patrol, often in a sunny clearing or field. On the other hand, we think it’s safe to say Tiger Spiketail perches infrequently.

Do other types of odonates live in the same habitat?

Seeps and small seep-fed streams in the forest are perfect places to look for Gray Petaltail dragonfly (Tachopteryx thoreyi), another habitat specialist found in Virginia, as well as spiketails such as Arrowhead and Tiger.

Photo used with written permission from Mike Boatwright.

Related Resources

Editor’s Note: My good friend and odonate hunting buddy Mike Boatwright and I collaborated to share some of the wisdom gleaned from our experiences hunting spiketail dragonflies in Virginia. Thanks, Mike — couldn’t have done it without you!

Copyright © 2022 Walter Sanford. All rights reserved.

The time is now!

January 4, 2022

Happy New Year! Let the yearning begin. Wait, what? Yep, I’m fighting feeling like I can’t wait for the start of the new odonate hunting season.

Realistically it will be a few months before adult dragonflies and damselflies are flying again, but that’s a good thing. Wait, did I just say that? Yes, and here’s why.

The odonate hunting “off season” provides a good opportunity to plan for the next campaign by making a list of target species and laying out when and where to look for them.

Why is it important to make a plan? Because the season starts slowly but explodes quickly. To illustrate my point, take a look at my Odonate Calendar for adult flight dates of dragonfly species for the month of February (shown below). Not much happening until the end of the month, right?

Dragonflies (VA Flight Dates) | February 2022

Now look at March (shown below). There’s an explosion of species beginning around the second week in March. The boom continues into July before slowing down noticeably in August.

Dragonflies (VA Flight Dates) | March 2022

Also notice many of the spring species of dragonflies are habitat specialists that require extra time and effort to find. So my advice is start planning now for a more productive and satisfying season of odonate hunting.

Related Resources

Both of the following resources feature online, interactive calendars for dragonflies and damselflies based upon Dr. Steve Roble’s excellent datasets for the Commonwealth of Virginia.

Copyright © 2022 Walter Sanford. All rights reserved.

Mouth parts – Tiger Spiketail exuvia

November 12, 2021

I revisited a photograph featured in a blog post published several years ago. I wanted to annotate the image to include information that I learned recently.

The following annotated image shows the face and mouth of an exuvia from a Tiger Spiketail dragonfly (Cordulegaster erronea) after its scoop-shaped face mask was pulled away from the head in order to count setae on the inner side of the prementum.

Cordulegaster erronea | exuvia (face and mouth)

There are two mandibles, one located on each side of the labrum. And there are two maxilla, one located below each mandible. Coarse setae make it challenging to see all of the parts clearly.

Sincere thanks to Marla Garrison for verifying my tentative identification of these mouth parts. And of course, thanks to Mike Boatwright for collecting and sharing the specimen with me.

Related Resources

Copyright © 2021 Walter Sanford. All rights reserved.

Yellow-sided Skimmer (terminal appendages)

August 24, 2021

Female and male Yellow-sided Skimmer dragonflies (Libellula flavida) were spotted at a small pond at an undisclosed location in Prince William County, Virginia USA.

Female

The first individual is a female, as indicated by her mostly yellow coloration and terminal appendages.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (female)

Female dragonflies have a pair of cerci (superior appendages) that have little or no function.

Mature male

The last individual is a mature male, as indicated by his light-blue pruinescence and terminal appendages.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (male)

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”).

Immature male Yellow-sided Skimmers look similar to females of the same species. Terminal appendages can be used to differentiate the sex of immature males and mature females.

Related Resource: Yellow-sided Skimmer (male and female) – a blog post by Walter Sanford.

Copyright © 2021 Walter Sanford. All rights reserved.

Anatomy of a male Tiger Spiketail

August 10, 2021

The following annotated image shows a Tiger Spiketail dragonfly (Cordulegaster erronea). This individual is a male, as indicated by his hamules, “indented” hind wings, and terminal appendages.

Hamules

Hamules? What are hamules?

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.

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. Some species of dragonflies and damselflies — such as Ashy Clubtail versus Lancet Clubtail and Southern Spreadwing versus Sweetflag Spreadwing, to name a few — can be differentiated/identified with certainty only by examining the hamules under magnification.

Photo used with written permission from Michael Powell.

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

Indented hind wings

Male members of many families of dragonflies have “indented” hind wings near the body, with some notable exceptions.

Hind wing venation and shape can identify the sex of most dragonflies. Petaltails, darners (except Anax), clubtails, spiketails, cruisers, and some emeralds. Wing shape isn’t helpful to sex baskettails since they are largely the same. They are different in Cordulia, Dorocordulia, Somatochlora and to a lesser degree, Neurocordulia. Source Credit: Ed Lam, author and illustrator of Damselflies of the Northeast.

Terminal appendages

Identifying female versus male dragonflies and damselflies can be challenging but it’s a little easier when you know how to differentiate their terminal appendages.

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”). Male dragonfly terminal appendages don’t look exactly the same for all species of dragonflies, but their function is identical.

Generally speaking, spiketail dragonflies have relatively small terminal appendages. That said, they must get the job done!

Related Resource: Tiger Spiketail dragonfly (male) – a blog post by Walter Sanford.

Copyright © 2021 Walter Sanford. All rights reserved.

 

Tiger Spiketail dragonfly (male)

August 7, 2021

Tiger Spiketail dragonfly (Cordulegaster erronea) was captured along a small stream at an undisclosed location in Prince William County, Virginia USA. The specimen was photographed and released unharmed.

The first few images show Michael Powell, my former friend and photowalking buddy, holding the dragonfly while I shot some photographs.

05 AUG 2021 | Prince William County, VA | Tiger Spiketail (male)

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

05 AUG 2021 | Prince William County, VA | Tiger Spiketail (male)

What a handsome face! Cue “Eye Of The Tiger” by Survivor.

05 AUG 2021 | Prince William County, VA | Tiger Spiketail (male)

The next image shows me holding the dragonfly so that Mike could take some photographs. Hold That Tiger. (Strike up the band!)

Photo used with written permission from Michael Powell.

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

Up, up, and away!

The last photograph shows the Tiger Spiketail “posed” au naturel on the trunk of a fallen tree. Mike and I chose that spot because it was one of only a few sunny places along the small forest stream. The Tiger flew away almost immediately after I released him, headed toward the tree canopy. Mike had time for one clear shot. Good thing, ‘cuz I had no opportunity to get a shot.

Photo used with written permission from Michael Powell.

The backstory

I went on my first Tiger safari during July 2018 when I visited a location in Fairfax County, Virginia that a friend shared with me in strictest confidence. Although I saw several Tiger Spiketail dragonflies, every individual was in flight and I was unable to shoot still photos and/or video — they were gone by the time I reached for my camera!

Every year for the next few years, the story was similar — I saw Tigers but had no photos/videos to verify my sightings. Eventually I came to the conclusion that I would need to capture a specimen with an insect net in order to take photographs.

Let me be perfectly clear — all things being equal I would prefer to photograph dragonflies perching naturally rather than netting them. Sometimes, as in this case, netting is the better way to go.

Rest assured I have great respect for the rare- to uncommon species of odonates. The Tiger Spiketail featured in this post was held in captivity no longer than absolutely necessary, and was handled gently at all times.

Our strategy

Mike and I arrived at the stream site sometime after 10 a.m. While I setup my 18” diameter collapsible insect net, Mike took the point a little farther downstream to look for a Tiger approaching our location. No more than 10 minutes after I was in position alongside the stream, Mike spotted a Tiger flying upstream in our direction.

I waited until the Tiger had almost reached the place where I was standing before I swung my net forward smoothly and was psyched to see the dragonfly go all the way into the net. I said to Mike, “I got it!”

From that point, I worked quickly to gently remove the dragonfly from the net so that Mike and I could take some photographs of this rare species.

Range map

The following map shows all official records for Cordulegaster erronea in the United States of America. Tiger Spiketail is a habitat specialist that is challenging to find.

Related Resources

Copyright © 2021 Walter Sanford. All rights reserved.

Gray Petaltail dragonfly (male)

July 13, 2021

A Gray Petaltail dragonfly (Tachopteryx thoreyi) was observed during a photowalk with Michael Powell along the shoreline of a small pond at an undisclosed location in Prince William County, Virginia USA.

Mike spotted the Gray Petaltail first, when we were on opposite sides of the pond. Mike was able to shoot a few photos before the dragonfly flew away and Mike moved on. I thought Mike gave up on the subject too quickly so I decided to use one of my tried and true strategies for finding and photographing odonates: Sit in a good spot and wait for the game to come to me.

I walked around to the other side of the pond and sat down on my small, lightweight camp stool about 12-15 feet from the place where Mike had seen the Gray Petaltail. Sure enough, the dragonfly returned to the same perch soon afterward!

The first photo is the “record shot,” that is, get a shot, any shot.

17 JUN 2021 | PNC. Wm. County | Gray Petaltail (male)

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

17 JUN 2021 | PNC. Wm. County | Gray Petaltail (male)

The dragonfly would perch briefly, then fly away.

17 JUN 2021 | PNC. Wm. County | Gray Petaltail (male)

The male dragonfly did the same thing repeatedly, always returning to a slightly different perch each time. Turns out he was hunting for food.

17 JUN 2021 | PNC. Wm. County | Gray Petaltail (male)

I would describe T. thoreyi as an “ambush predator” — sometimes Gray Petaltail hunts for prey by waiting for other flying insects to pass by and ambushing them aerially when they do. Like the crane fly shown below that the Gray grabbed before landing on my bucket hat.

Photo used with written permission from Michael Powell.

I was happy to provide a white table cloth for a classy dining experience with one of my favorite species of dragonflies.

Habitat

For habitat-specific odonates such as T. thoreyi, it’s all about location, location, location. “Gray Petaltail dragonfly (male)” is another blog post by Walter Sanford that provides actionable intel regarding ideal habitat for Grays.

Range map

The following map shows all official records for Tachopteryx thoreyi in the United States of America. Gray Petaltail is a habitat specialist that is challenging to find.

Related Resources

  • Tachopteryx thoreyi Gray Petaltail on NatureServe Explorer. The conservation status for T. thoreyi in Virginia is “Apparently Secure (S4).” That’s good news. The bad news: That doesn’t mean it’s easy to find.
  • Gray Petaltail dragonfly (male)” – another blog post by Walter Sanford that provides actionable intel regarding ideal habitat for Grays.

Copyright © 2021 Walter Sanford. All rights reserved.

Yellow-sided Skimmer (female, male)

June 25, 2021

Thanks to a tip from fellow odonate enthusiast Michael Ready, I was able to add another species of dragonfly to my life list recently: Yellow-sided Skimmer dragonfly (Libellula flavida).

Female

The first Yellow-sided Skimmer dragonfly that I spotted was perched along the shoreline of a small pond at an undisclosed location in Prince William County, Virginia USA. This individual is a female, as indicated by her terminal appendages.

Female Yellow-sided Skimmers have a pair of flanges beneath their eighth abdominal segment that are used to scoop and hold a few drops of water when laying eggs (oviposition), hence the family name “Skimmer.” Remember that all dragonflies and damselflies have a 10-segmented abdomen, numbered from front to back.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (female)

I followed the female from one perch to another, “working the shot.” The next two photos are full-frame (4,000 x 3,000 pixels), that is, uncropped.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (female)

Notice the amber color near the leading edge of her wings, a good field mark for L. flavida.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (female)

Male

According to Dr. Steve Roble’s excellent datasets for the Commonwealth of Virginia, the adult flight period for Yellow-sided Skimmer is from May 15 to September 21.

By mid-June most males, including this one, are completely covered by light-blue pruinescence that obscures the yellow coloration on the sides of their thorax. Look closely at the full-size version of the following photo and you should see the amber color near the leading edge of his wings.

17 JUN 2021 | PNC. Wm. County | Yellow-sided Skimmer (male)

Habitat

A small, seep-fed pond located in the forest provides ideal habitat for Yellow-sided Skimmer.

Habitat: Boggy ponds, seeps, slow streams, and weedy ditches. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Location 9094). Princeton University Press. Kindle Edition.

23 MAY 2018 | PNC. Wm. County | small, seep-fed pond

Notice the fallen tree that lies between the foreground and the pond in the background, nearly perpendicular to the stream. The tree is a barrier that slows the flow of the stream, creating the type of boggy, weedy habitat that Yellow-sided Skimmer prefers.

Range maps

Not all species of Skimmers are as common as I tend to think. For example, the following map shows all official records for Libellula flavida in the United States of America. As you can see, Yellow-sided Skimmer is a relatively uncommon species of odonate.

Zooming in to reveal the details shows few records reported for Northern Virginia, where I live.

What are the take-aways?

Many species of dragonflies in the Family Libellulidae (Skimmers) are habitat generalists and relatively easy to find almost anywhere there is water. In contrast, I think it’s fair to say Yellow-sided Skimmer is a habitat specialist that is challenging to find.

Related Resource: Libellula flavida Yellow-sided Skimmer on NatureServe Explorer. The conservation status for L. flavida in Virginia is “Vulnerable (S3).”

Copyright © 2021 Walter Sanford. All rights reserved.

Gray Petaltail dragonflies (female, male)

June 18, 2021

Several Gray Petaltail dragonflies (Tachopteryx thoreyi) were observed at an undisclosed location in Fairfax County, Virginia USA. Only two individuals perched long enough to pose for photos.

The first one I spotted was perched relatively high on a tree on the earthen berm of a small pond. This individual is a female, as indicated by her rounded hind wings and terminal appendages. I was able to take just four photos of the female before she flew toward the top of the same tree.

05 JUN 2021 | Fairfax County, VA | Gray Petaltail (female)

Quite a while later, I spotted another Gray Petaltail land on another tree briefly, and by “briefly” I mean briefly. I had time for one shot as I was approaching the tree slowly, and just like that, the dragonfly flew toward the top of another tree. This individual is a male, as indicated by his “indented” hind wings and terminal appendages.

05 JUN 2021 | Fairfax County, VA | Gray Petaltail (male)

As it turns out, the preceding male was the last Gray Petaltail I saw for the day. Mike Powell and I had noticed the Grays seemed to be spending a lot of time in the tree canopy. I speculated their atypical behavior might be caused by the peak- or near-peak activity of Brood X Peridical Cicadas. Mike was, as always, skeptical of my speculation.

A little more than a week later, a post by Harold Bancroft White in the Northeast Odonata Facebook group seems to provide some support for my speculative theory. I like it when Gray Petaltails perch near the ground, so I hope their new hunting habit isn’t imprinted on the next generation!

Copyright © 2021 Walter Sanford. All rights reserved.

It’s all about habitat, habitat, habitat.

April 23, 2021

Seeps and small streams in the forest are perfect places to look for habitat specialist dragonflies such as petaltails and spiketails.

An old place revisited.

The following photograph of a forest seep has been featured in my blog at least once in the past. The seep feeds a small pond; Gray Petaltail dragonflies (Tachopteryx thoreyi) can be found feeding and perching in sunny spots around the pond during late-May and early-June.

23 MAY 2018 | Prince William County, VA | forested seep

The seep is the habitat where Gray Petaltail larvae live most of their lives, not the pond. I always wondered how so many adult petaltails could emerge from this relatively small seep.

Turns out Michael Powell, my good friend and photowalking buddy, must have been wondering the same thing because he explored the area upstream from the small seep shown above and discovered several more seeps located close to the one near the pond.

The next photo shows Mike resting on a log along the edge of one of the seeps, near the confluence of two small streams. Notice the patch of skunk cabbage (Symplocarpus foetidus) growing in the seep — a good sign that you might be looking at habitat suitable for Gray Petaltail.

13 APR 2021 | Prince William County, VA | forested seep

A new place worth exploring further.

Mike also discovered another small stream in the forest when he was exploring for Uhler’s Sundragon (Helocordulia uhleri). The stream is located at the approximate midpoint between two trails, so I nicknamed it “Middle Creek.” Clever, huh? Note the patch of skunk cabbage growing in a seep alongside the stream. Did an alarm just go off in your head?

13 APR 2021 | Prince William County, VA | forested stream and seep

Mike and I are eager to explore the stream further, mainly looking for Gray Petaltail during late spring. Several species of spiketails might be found there as well.

Copyright © 2021 Walter Sanford. All rights reserved.


%d bloggers like this: