Posts Tagged ‘Family Libellulidae (Skimmers)’

Common Whitetail (immature males)

May 7, 2018

A first-of-season Common Whitetail dragonfly (Plathemis lydia) was spotted perching on the ground near a vernal pool at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is an immature male, as indicated by his terminal appendages, brown colored abdomen, and pattern of wing spots.

30 APR 2018 | Huntley Meadows Park | Common Whitetail (immature male)

Another immature male was spotted along an informal trail at a remote location in the park.

30 APR 2018 | Huntley Meadows Park | Common Whitetail (immature male)

Young male Common Whitetails begin to develop white pruinescence that changes the color of their abdomen from brown to white, hence the common name for this species.

Sexing Common Whitetail dragonflies

For many of the common species of odonates found in Northern Virginia, I created a collection of annotated guides that illustrates how to differentiate gender by looking at terminal appendages. The difference in the pattern of wings spots for male and female Common Whitetails is sufficient to identify gender.

Copyright © 2018 Walter Sanford. All rights reserved.

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Common Whitetail dragonfly (female)

May 5, 2018

Common Whitetail dragonflies (Plathemis lydia) are like bad party guests: they are among the first to arrive and last to leave. Nonetheless, it was good to see one on a day when almost no adult odonate species were observed.

30 APR 2018 | Huntley Meadows Park | Common Whitetail (female)

A Common Whitetail was spotted perching on a man-made brush pile near a vernal pool at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a female, as indicated by her terminal appendages and pattern of wing spots.

30 APR 2018 | Huntley Meadows Park | Common Whitetail (female)

The “schmutz” that appears at the tip of her abdomen is probably excrement. Hey, schmutz happens!

Copyright © 2018 Walter Sanford. All rights reserved.

Blue Corporal (teneral males)

May 3, 2018

Several teneral male Blue Corporal dragonflies (Ladona deplanata) were spotted near Painted Turtle Pond during a photowalk at at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA.

Teneral/immature/young male Blue Corporals look similar to females of the same species. Terminal appendages can be used to differentiate gender: males have three (3) appendages; females have two (2).

Some of the ground cover is charred from a recent controlled burn at Occoquan Bay NWR.

The common name for Blue Corporal is derived from two cream-colored stripes that appear on the front of the thorax, similar to the two stripes that signify the rank of corporal in the military. As a mature male, those stripes will be partially obscured by dark blue pruinescence.

Related Resource: Blue Corporal (teneral females).

Copyright © 2018 Walter Sanford. All rights reserved.

Blue Corporal (teneral females)

May 1, 2018

Lots of Blue Corporal dragonflies (Ladona deplanata) were spotted near Painted Turtle Pond at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. This is the first time the author has observed Blue Corporal at Painted Turtle Pond.

Both individuals featured in this post are teneral females, as indicated by their tenuous wings and terminal appendages.

Female 1

The first female was spotted perching on vegetation near the shoreline of Painted Turtle Pond. Some of the ground cover is charred from a recent controlled burn at Occoquan Bay NWR.

The common name for Blue Corporal is derived from two cream-colored stripes that appear on the front of the thorax, similar to the two stripes that signify the rank of corporal in the military.

Notice the abdomen of this female seems to be bent slightly to the right (facing forward). This malformation probably occurred during emergence.

Female 2

The last female was spotted perching on the gravel road leading to Painted Turtle Pond. The purple rock located in the upper-right corner of the photo might contain the mineral fluorite.

Like many teneral dragonflies, if not most, this individual was quite skittish. I followed the female to two locations before calling the photowalk a wrap.

Related Resource: Blue Corporal (teneral males).

Copyright © 2018 Walter Sanford. All rights reserved.

Previews of coming attractions

March 28, 2018

Several test photos were taken for an upcoming identification guide for exuviae from Slaty Skimmer dragonfly (Libellula incesta).

The exuvia has a mask-like labium with smooth crenulations, indicating this specimen is a member of the Family Libellulidae (Skimmers), the largest family of dragonflies.

No. 1 | Libellula incesta | exuvia (face-head-dorsal)

Also notice the exuvia has “pointed” eyes, rather than “rounded” eyes like the exuvia from a Carolina Saddlebags dragonfly (Tramea carolina) shown below.

No. 2 | Tramea carolina | exuvia (face-head)

The pointed- versus rounded eyes dichotomy is a somewhat subjective decision, but if you make the right choice then this marker can be used to narrow the range of possible Libellulidae genera.

Exuviae from three genera of Libellulidae have pointed eyes: Libellula (18 species); Orthemis (3 species); and Plathemis (2 species). Slaty Skimmer (Libellula incesta) is one of 18 species in the genus Libellula.

Exuviae from all other genera of Libellulidae have rounded eyes.

No. 3 | Libellula incesta | exuvia (dorsal)

This specimen needs to be rehydrated/relaxed in order to remove some distracting debris and reposition the legs for better photo poses.

No. 4 | Libellula incesta | exuvia (ventral)

To be continued…

The Backstory

A Slaty Skimmer dragonfly (Libellula incesta) nymph was collected by Bob Perkins on 29 May 2017 along Pine Creek in Carroll County, Virginia USA. The nymph was reared in captivity until it emerged on 29 June 2017 and metamorphosed into an adult male. This specimen is the exuvia from the nymph.

Copyright © 2018 Walter Sanford. All rights reserved.

Predator and prey

February 8, 2018

A Black and Yellow Argiope (Argiope aurantia) was spotted during a photowalk along Deephole Point Road at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. A female Common Whitetail dragonfly (Plathemis lydia) is trapped in the spider web.

“Eat or be eaten” is perhaps the most fundamental law of nature. Predator-prey relationships can change suddenly: one minute a predator, such as a dragonfly, is hunting for its next meal; next minute the dragonfly becomes the prey and is a meal for another predator, such as a spider, elsewhere in the food web.

Copyright © 2018 Walter Sanford. All rights reserved.

Male Blue-faced Meadowhawk dragonflies

February 4, 2018

On the same day that I saw a male Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) with an eye injury, one or more other males were photographed at the same location in Huntley Meadows Park, Fairfax County, Virginia USA.

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male)

Please look at the full-size version of each photo in order to fully appreciate these handsome little devils!

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male)

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male)

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male)

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male)

Copyright © 2018 Walter Sanford. All rights reserved.

Eye injury

January 31, 2018

A Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) was spotted near a vernal pool at remote location in Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male, as indicated by his terminal appendages.

When I post-processed the RAW images of the male dragonfly I noticed he has an eye injury, highlighted in the following annotated image.

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male, with eye injury)

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

The eye injury can be seen in two more photos of the same male.

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male, with eye injury)

22 OCT 2017 | HMP | Blue-faced Meadowhawk (male, with eye injury)

Related Resource: Eye injury, a blog post by Walter Sanford, featuring photos of a female andromorph Blue-faced Meadowhawk dragonfly spotted on 18 September 2013 along the boardwalk of the central wetland area at Huntley Meadows Park.

Copyright © 2018 Walter Sanford. All rights reserved.

Slaty lady

January 27, 2018

Mike Powell and I were searching for Fine-lined Emerald dragonflies at Occoquan Bay National Wildlife Refuge, Prince William County, Virginia USA. As we were walking along one of many gravel trails at the park, I spotted a dragonfly perching atop an unusually tall grass stem.

16 SEP 2017 | Occoquan Bay NWR | Slaty Skimmer (mature female)

This individual is a mature female Slaty Skimmer dragonfly (Libellula incesta). Although Mike and I were disappointed we hadn’t found a Fine-lined Emerald, I was happy to shoot a photograph worthy of my Odonart Portfolio.

Related Resources

Copyright © 2018 Walter Sanford. All rights reserved.

Lunch time

January 21, 2018

A Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) was spotted at ~12:13 p.m. near a vernal pool at a remote location in Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male, eating an unknown species of winged insect.

25 OCT 2017 | HMP | Blue-faced Meadowhawk (male, eating)

The first photo is the scene-setter.

25 OCT 2017 | HMP | Blue-faced Meadowhawk (male, eating)

The last two photos are cropped so that the predator and prey are more prominent. The dragonfly barely moved from the first-to-last photos; the position of the butterfly/moth moved slightly as it was eaten.

25 OCT 2017 | HMP | Blue-faced Meadowhawk (male, eating)

Did you notice there are three insects shown in each photo? Perhaps the fly is an opportunist, waiting to clean-up the leftovers from the dragonfly’s lunch.

Copyright © 2018 Walter Sanford. All rights reserved.


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