Posts Tagged ‘Family Lestidae (Spreadwings)’

Slender Spreadwing damselfly (female)

October 16, 2020

Michael Powell spotted a Slender Spreadwing damselfly (Lestes rectangularis) perched on greenbriar vine in a wetland area alongside the gravel trail we were following out of Huntley Meadows Park, located in Fairfax County, Virginia USA.

This individual is a female, as indicated by her coloration and terminal appendages. Notice the tip of her abdomen is enlarged because of her reproductive anatomy, including an ovipositor.

Female Slender Spreadwing can be confused with female Southern Spreadwing damselflies. Several key field marks are used to differentiate the two species.

Blue shoulder stripes, slender abdomen, the ratio of abdominal segments seven and nine (S7 and S9), and whitish wing tips all point to Slender Spreadwing. S7 is more than twice the length of S9 in Slender, covered in Ed Lam’s book. Source Credit: Dr. Michael Moore, a professor (retired) in the Department of Biological Sciences at University of Delaware and odonate expert extraordinaire. Dr. Moore’s new Web site is a treasure trove of helpful resources.

Related Resource: Damselflies of the Northeast, by Ed Lam (author and illustrator).

Copyright © 2020 Walter Sanford. All rights reserved.

MYN – Zygoptera exuvia (ventral-lateral view)

March 27, 2020

A Zygoptera exuvia (species unknown) was collected on 21 May 2019 alongside a small pond at an undisclosed location in Prince William County, Virginia USA.

This individual is a member of Family Lestidae (Spreadwings), as indicated by the unique shape of its prementum — it reminds me of a rattle (musical instrument).

The rudimentary ovipositor that is faintly visible on the ventral side of abdominal segment nine (S9) indicates this specimen is a female.

21 MAY 2019 | Zygoptera exuvia (ventrallateral view) | female

My what long antennae you have, Grandma! The better to sense you, my dear.

Related Resources

Tech Tips

This subject was photographed against a pure white background (255, 255, 255) using the “Meet Your Neighbours” (MYN) technique.

Three photos were used to create a composite image: one photo focused on the head; another focused on the wing pads; and a third focused on abdominal segment six (S6).

Copyright © 2020 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.

Great Spreadwing (practice oviposition)

October 15, 2017

This gallery — named “practice oviposition” (egg-laying) — features a six-photo time series of a female Great Spreadwing damselfly (Archilestes grandis).

Female Great Spreadwing damselflies, like all female odonates, have two cerci (sing. cercus), superior appendages that have little or no function. Also notice two styli (sing. stylus), structures that serve as sensors (like “curb feelers“) in egg positioning during oviposition.

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

The female uses her styli to guide the ovipositor into position, as shown in the next two photos.

In this case, I saw no evidence that the ovipositor actually penetrated the tree twig. I think this was a practice run in preparation for the real thing, as the title of this blog post says.

Copyright © 2017 Walter Sanford. All rights reserved.

Great Spreadwing damselfly (female)

October 13, 2017

A Great Spreadwing damselfly (Archilestes grandis) was spotted near a vernal pool at a remote location in Huntley Meadows Park, Fairfax County, Virginia USA.

This individual is a female, as indicated by her terminal appendages and external reproductive anatomy, including two styli and an ovipositor.

Sometimes I struggle to choose between two similar images, so I decided to post both photos.

The following photo captured the “feel” of the morning light especially well.

The next two photos are among my favorites in this set.

This female was a more cooperative model after she moved to a perch on a man-made brush pile that provides habitat and shelter for many types of animals.

Female Great Spreadwing damselflies, like all female odonates, have two cerci (sing. cercus), superior appendages that have little or no function. Also notice two styli (sing. stylus), structures that serve as sensors (like “curb feelers“) in egg positioning during oviposition.

My next blog post will feature a six-photo time series that I named “practice oviposition” (egg-laying).

Copyright © 2017 Walter Sanford. All rights reserved.

Pop quiz answer key

June 9, 2017

Perhaps the simplest way to provide answers to the recent pop quiz — in which readers were challenged to identify the gender of two Southern Spreadwing damselflies (Lestes australis) — is to show what the teneral/immature male (shown in my last post) will look like when he’s a little older.

The following photos show Southern Spreadwings spotted at Mason Neck West Park, Fairfax County, Virginia USA. Both individuals are male, as indicated by their terminal appendages and blue coloration.

Both photographs of the male Southern Spreadwings were taken at an angle that shows their terminal appendages clearly.

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”).

In contrast, female damselflies have two cerci (sing. cercus), superior appendages that have little or no function. Notice the two “nubs” at the tip of the abdomen, as shown in the photo of the female Southern Spreadwing that was featured in the pop quiz.

Editor’s Notes: There are four families of damselflies (Suborder Zygoptera) in the United States of America, although only three families occur in the mid-Atlantic region: Family Calopterygidae (Broad-winged Damselflies)Family Coenagrionidae (Narrow-winged Damselflies); and Family Lestidae (Spreadwings).

Male Broad-winged Damselflies and Spreadwing Damselflies have terminal appendages that are large enough to see with the unaided eye. Generally speaking, both male and female Narrow-winged Damselflies are too small to see their terminal appendages clearly in most photographs.

Copyright © 2017 Walter Sanford. All rights reserved.

Pop quiz

June 7, 2017

OK, it’s time to assess what you’ve learned about damselflies by following my blog.

Two Southern Spreadwing damselflies (Lestes australis) were photographed on the same day at the same location. Both damselflies are teneral/immature, that is, they are relatively young. One is a female; one is a male. Can you identify the gender of the damselflies shown in the following photos?

I’ll give you a hint: Examine their terminal appendages by looking at the full-size version of both photos.

No. 1

No. 2

Editor’s Note: The answer key will be published in my next post.

Copyright © 2017 Walter Sanford. All rights reserved.

Voltinism, revisited

April 30, 2017

Voltinism is a term used in biology to indicate the number of broods or generations of an organism in a year. Source Credit: Wikipedia.

Some species of odonates, such as Southern Spreadwing damselfly (Lestes australis), can be multivoltine.

Huntley Meadows Park

Long-term monitoring of a vernal pool at Huntley Meadows Park has shown Southern Spreadwing is multivoltine at that site.

Mason Neck West Park

Males and females from a single brood of Southern Spreadwing were observed during Fall 2016 at Mason Neck West Park; males from another brood were spotted at the same location on 05 April 2017 and again on 18 April 2017. This evidence suggests Southern Spreadwing is multivoltine at Mason Neck West Park (MNWP). Further field observations are necessary to determine whether more than two broods occur at this location.

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

Please look at the full-size versions of the preceding photos in order to appreciate the “fresh” coloration that seems to be a noticeable characteristic for many species of recently-emerged odonates.

Copyright © 2017 Walter Sanford. All rights reserved.

Slender Spreadwing damselflies (females)

March 25, 2017

Two female Slender Spreadwing damselflies (Lestes rectangularis) were spotted during a photowalk around a vernal pool in the forest at Huntley Meadows Park.

No. 1

No. 2

Notice the second individual is bluer in color. Coloration is variable, so it’s better to look at other field markers when making an identification.

Copyright © 2017 Walter Sanford. All rights reserved.

Arachnids 2, Odonates 0

March 23, 2017

A spider was observed preying upon a teneral damselfly at a vernal pool in Huntley Meadows Park. The genus/species of the spider is uncertain; the damselfly appears to be a female Slender Spreadwing (Lestes rectangularis).

31 MAY 2016 | Huntley Meadows Park | spider preying upon damselfly

According to experts on the BugGuide Facebook group, the spider is probably an unknown species from the Family Araneidae (Orb Weavers).

Post Update: Ashley Bradford, a local arachnid expert and excellent all-around amateur naturalist, identified the spider as an Arabesque Orbweaver (Neoscona arabesca). Thanks, Ashley!

31 MAY 2016 | Huntley Meadows Park | spider preying upon damselfly

Aperture Priority mode was used for the next photo, in order to increase the depth of field. As you can see, the depth of field at f/8.0 was insufficient for both the damselfly and spider to be in focus.

31 MAY 2016 | Huntley Meadows Park | spider preying upon damselfly

A dragonfly was trapped in a spider web at Hidden Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. The dragonfly, possibly an immature male Blue Dasher (Pachydiplax longipennis), is infested with parasitic red water mites.

22 JUN 2016 | Meadowood Recreation Area | dragonfly in spider web

Copyright © 2017 Walter Sanford. All rights reserved.


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