Archive for September, 2013

Common Green Darner dragonfly (male)

September 29, 2013

The following photographs show a Common Green Darner dragonfly (Anax junius) perching in a shrub near the end of the boardwalk at Huntley Meadows Park. This individual is a male, as indicated by its blue abdomen.

Common Green Darner dragonfly (male) Common Green Darner dragonfly (male)

It is uncommon to spot a darner perching. Dragonflies are classified as either “fliers” or “perchers,” based upon their feeding habits. Common Green Darners are fliers, foraging by “hawking” other flying insects. (Note: Darners are called hawkers in the United Kingdom.) Common Green Darners are migratory dragonflies — perhaps Huntley Meadows Park was a rest stop along this specimen’s southward migration route.

Copyright © 2013 Walter Sanford. All rights reserved.

Great Blue Skimmer dragonfly (adult female)

September 27, 2013

The following photographs show a Great Blue Skimmer dragonfly (Libellula vibrans) spotted at Huntley Meadows Park, a 1,425 acre wetland area in Fairfax County, Virginia USA. This individual is an adult female, resting after mating.

Great Blue Skimmer dragonfly (adult female, resting after mating) Great Blue Skimmer dragonfly (adult female, resting after mating)

Copyright © 2013 Walter Sanford. All rights reserved.

Great Blue Skimmer dragonflies (mating pair)

September 25, 2013

The following photographs show a mating pair of Great Blue Skimmer dragonflies (Libellula vibrans) spotted in the central wetland area at Huntley Meadows Park. The pair is shown “in wheel.” All dragonflies and damselflies have a 10-segmented abdomen: male dragonfly secondary genitalia are located in segments two and three (2 and 3); female genitalia in segment eight (8). Therefore, the male dragonfly is on top; the female is on the bottom.

Great Blue Skimmer dragonflies (mating pair) Great Blue Skimmer dragonflies (mating pair)

Copyright © 2013 Walter Sanford. All rights reserved.

Common Ribbonsnake (eating a frog)

September 23, 2013

Common Ribbonsnake eating a frog

The preceding photograph shows a Common Ribbonsnake (Thamnophis sauritus sauritus) eating a Green Frog (Lithobates clamitans), spotted along the boardwalk that goes through the central wetland area at Huntley Meadows Park.

Copyright © 2013 Walter Sanford. All rights reserved.

Northern Watersnake (eating a frog)

September 21, 2013

The following photographs show a Northern Watersnake (Nerodia sipedon sipedon) eating an American Bullfrog (Lithobates catesbeianus), spotted along the boardwalk that goes through the central wetland area at Huntley Meadows Park.

Northern Watersnake eating a frog Northern Watersnake eating a frog

The following slideshow features a time-series of five photos showing the predator slowly swallowing its prey. Frogs make an unmistakable distress call when they are in the jaws of a snake — once you’ve heard it you’ll never forget it!

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Human interest sidebar:Peristalsis is an amazing thing,” commented one of the people watching the snake-eats-frog spectacle. I turned to the woman and said, “You must be some sort of professional biologist, because the word ‘peristalsis’ isn’t in the vocabulary of most people.” Turns out she is currently working as a veterinarian; her former job was at the Smithsonian’s National Zoo. Fascinating woman with a beautiful baby — hope to see her at the park again!

Copyright © 2013 Walter Sanford. All rights reserved.

Twelve-spotted Skimmer dragonfly (female)

September 19, 2013

The following photograph shows a Twelve-spotted Skimmer dragonfly (Libellula pulchella) spotted along the boardwalk that goes through the central wetland area at Huntley Meadows Park. This individual is an adult female, as indicated by its coloration and the terminal appendages at the end of its abdomen.

Twelve-spotted Skimmer dragonfly (adult female)

Female Twelve-spotted Skimmer dragonflies appear very similar to female Common Whitetail dragonflies (Plathemis lydia), such as the one shown below, spotted at Meadowood Recreation Area.

Common Whitetail dragonfly (female)

Although males quite different, female Common Whitetail poses identification problem, as she has same 12 wing spots. In addition to being distinctly smaller, female Whitetail has series of yellowish-whitish spots not contacting edge of each abdominal segment, whereas female Twelve-spotted has continuous parallel yellow stripes on either edge of abdomen. In side view of thorax, female Whitetail has additional yellow dot in front of anterior yellow stripe, lacking in Twelve-spotted. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 9017-9021). Princeton University Press. Kindle Edition.

Look closely at the pattern of wing spots for the female Common Whitetail, in particular, the middle spots on each wing. Notice the shape of each middle spot forms a “spike” that points toward the body of the dragonfly. In contrast, the middle wing spots for female Twelve-spotted Skimmer aren’t “spiked.” An excellent blog post by DSA member Jim Johnson, entitled “ID Challenge #3 Answer,” illustrates the difference in the pattern of wing spots for these two species (using proper terminology).

Related Resources: Digital Dragonflies, presenting high-resolution digital scans of living dragonflies.

  • Genus Libellula | Libellula pulchella | Twelve-spotted Skimmer | female | top view
  • Genus Libellula | Libellula pulchella | Twelve-spotted Skimmer | female | side view
  • Genus Libellula | Libellula lydia [sic] | Common Whitetail | female | top view

Copyright © 2013 Walter Sanford. All rights reserved.

Twelve-spotted Skimmer dragonfly (male)

September 17, 2013

The following gallery shows a Twelve-spotted Skimmer dragonfly (Libellula pulchella) spotted along the boardwalk that goes through the central wetland area at Huntley Meadows Park. This individual is an adult male, as indicated by its distinctive pattern of wing spots, pruinescence that covers its abdomen completely, and the terminal appendages at the end of its abdomen.

I love a good head-tilt! (See Photos 3-4.)

Copyright © 2013 Walter Sanford. All rights reserved.

Twelve-spotted Skimmer dragonfly (young male)

September 15, 2013

The following gallery shows a Twelve-spotted Skimmer dragonfly (Libellula pulchella) spotted along the boardwalk that goes through the central wetland area at Huntley Meadows Park. This individual is a young male, as indicated by its distinctive pattern of wing spots, incomplete pruinescence, and the terminal appendages at the end of its abdomen. Notice that the Twelve-spotted Skimmer perches on four of six legs, with the two front legs curled around its head.

Copyright © 2013 Walter Sanford. All rights reserved.

Black Saddlebags dragonfly (young male)

September 13, 2013

The following photos show a Black Saddlebags dragonfly (Tramea lacerata). This specimen was spotted in a field located between the Pollinator Garden and Enchanted Pond, Meadowood Recreation Area, Fairfax County, Virginia USA. I think this individual is a young male. Expert opinions are invited and welcome!

Black Saddlebags dragonfly (female) Black Saddlebags dragonfly (female)

Editor’s Note: Ed Lam, author and illustrator of Damselflies of the Northeast, commented on this post via the Facebook Northeast Odonata group.

Your dragonfly is indeed a young male. The form of the cerci is different from the female’s. Also you can see the pale epiproct which the female lacks.

Thanks for your help, Ed!

Copyright © 2013 Walter Sanford. All rights reserved.

Halloween Pennant dragonfly (male)

September 11, 2013

The following photo gallery features a Halloween Pennant dragonfly (Celithemis eponina) spotted at Meadowood Recreation Area on 29 August 2013. This individual is a male, as indicated by its coloration and terminal appendages.

Copyright © 2013 Walter Sanford. All rights reserved.