Identifying dragonfly larvae to family

A couple of odonate exuviae were spotted in the bioswale (when it still retained water) at the head-end of the Hike-Bike Trail, Huntley Meadows Park. Both specimens are dragonfly exuvia, slightly less than 3/4″ long. I shot some quick-and-dirty still photos of the pair, as well as two sets of macro photos focusing on key anatomical parts.

Then I watched (and transcribed) the instructional video “Identifying dragonfly larva to family.” Be forewarned: Although the identification process is vocabulary-rich, the prerequisite terminology is well-illustrated in the video. Here’s the decision tree I used to make a tentative identification of the family.

Turns out I was correct — the exuviae are members of the Family Libellulidae (Skimmers)! Thanks to aquatic entomologist Celeste Searles Mazzacano, Ph.D., for verifying my tentative identification. The next (bigger) challenge: Learn how to identify odonate exuviae to the genus and species level.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 800| 400mm (600mm, 35mm equivalent) | 0 ev | f/11 | 1/250s

The first two photos were taken using a Fujifilm X-T1 digital camera and Fujinon XF100-400mm telephoto zoom lens set for 400mm.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 800| 400mm (600mm, 35mm equivalent) | 0 ev | f/11 | 1/250s

The next set of photos was taken using a Raynox DCR-250 close-up filter with my tripod-mounted Panasonic Lumix DMC-FZ150 superzoom digital camera; the scene was lighted using the built-in pop-up flash and Nissin i40 external flash (off-camera, in video mode).

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 28mm (155mm, 35mm equivalent) | -1.3 ev | f/7.1 | 1/3s

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 28mm (155mm, 35mm equivalent) | -1.3 ev | f/7.1 | 1/160s

The following photo is my favorite in this subset.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 57mm (318mm, 35mm equivalent) | -1.3 ev | f/7.1 | 1/250s

Notice the teeth on the margins of the labium are relatively smooth.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 55mm (304mm, 35mm equivalent) | -1.3 ev | f/7.1 | 1/250s

The last set of photos was taken using a Raynox DCR-250 close-up filter with my tripod-mounted Panasonic Lumix DMC-FZ150 superzoom digital camera; the scene was lighted using an off-camera Sunpak LED-160 Video Light (with a white translucent plastic filter) and Nissin i40 external flash (off-camera, in video mode).

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 56mm (311mm, 35mm equivalent) | -1 ev | f/7.1 | 1/10s

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 57mm (318mm, 35mm equivalent) | -1 ev | f/7.1 | 1/8s

The following photo is my favorite in this subset.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 30mm (164mm, 35mm equivalent) | -1 ev | f/7.1 | 1/6s

The last two shots are close-ups of the anal pyramid. Notice the cerci are less than half the length of paraprocts.

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 28mm (158mm, 35mm equivalent) | -1 ev | f/7.1 | 1/8s

A couple of odonate exuviae spotted at Huntley Meadows Park, Fairfax County, Virginia USA.

ISO 100| 56mm (311mm, 35mm equivalent) | -1 ev | f/7.1 | 1/8s

Related Resources:

Copyright © 2016 Walter Sanford. All rights reserved.

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2 Responses to “Identifying dragonfly larvae to family”

  1. laura lecce Says:

    I’ve only ever seen this left behind by cicada’s. Very cool to see the dragonfly version. Great photos, it’s amazing to see all the tiny details.

    • waltersanford Says:

      Thanks, Laura! The depth-of-field is so shallow in macro photos that I need to create some composite images using a photographic process called “focus stacking.” In this case, “single slice” images are sufficient for the purpose of identifying the exuviae.

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