Posts Tagged ‘Broad-winged Damselflies’

American Rubyspot damselfly exuvia

March 12, 2018

An American Rubyspot damselfly (Hetaerina americana) nymph was collected by Bob Perkins on 06 August 2017 along the New River in Grayson County, Virginia USA. The nymph was reared in captivity, albeit briefly, until it emerged on 09 August 2017.

This individual is a member of the Family Calopterygidae (Broad-winged Damselflies), as indicated by the length of antenna segment 1 (shown below). See Hetaerina americana exuvia for a more detailed explanation.

No. 1 | Hetaerina americana | exuvia (dorsal)

If you look closely at the full-size version of both photos, then you should notice the specimen is covered by a lot of fibers of unknown origin.

That nymph was in the final instar when I collected it. Therefore it didn’t shed the algae and debris that had collected on its bristles. Source Credit: Personal communication with Bob Perkins.

A quick look at the prementum (below) shows the labial cleft, a key field mark for verifying the species, is obscured by some of the “debris” that Bob mentioned. As of this writing, the exuvia is soaking in a soapy water bath in the hope that it can be cleaned sufficiently to see that field mark clearly.

No. 2 | Hetaerina americana | exuvia (ventral)

To be continued

Tech Tips

The following equipment was used to shoot Photo No. 1 and 2: Canon EOS 5D Mark II digital camera, in manual mode; Kenko 20mm macro automatic extension tubeCanon EF100mm f/2.8L Macro lens (set for manual focus); and Canon MT-26EX-RT Macro Twin Lite.

Two Sunpak LED-160 Video Lights (each with a white translucent plastic filter) were used for both photos.

Adobe Photoshop CC 2017 was used to annotate both images.

Copyright © 2018 Walter Sanford. All rights reserved.

American Rubyspot damselfly (female)

July 27, 2017

An American Rubyspot damselfly (Hetaerina americana) was spotted during a photowalk along Bull Run in Fairfax County, Virginia USA. As far as I know, this is the first official record for American Rubyspot at this location.

This individual is a female, as indicated by her terminal appendages and ovipositor.

21 JUN 2017 | Fairfax County, VA | American Rubyspot (female)

Notice one of the damselfly’s wings is either malformed or injured. She was able to fly, although it seemed to be a struggle.

The Backstory

The damselfly landed on my thigh a few minutes before the preceding photograph was taken. It was like she was pleading with me to help her, although I admit I tend to project my thoughts onto the odonates I photograph. I would have tried to unfold her wing, but I never had an opportunity. Two teenage girls and a bear-sized dog startled me! (I never heard/saw them approaching. The girls told me their dog is a Long Hair German Shepherd.) When I flinched the damselfly flew to the perch shown above, just beyond my reach.

Copyright © 2017 Walter Sanford. All rights reserved.

How to Identify Damselfly Exuviae to Family

March 11, 2017

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).

Pattern recognition can be used to tentatively identify damselfly larvae/exuviae to the family level: the shape of the prementum is characteristic for each of the three families; mnemonics can be used to remember each distinctive shape.

Family Calopterygidae (Broad-winged Damselflies)

Family Calopterygidae features a prementum with a shape that looks somewhat similar to Family Coenagrionidae. Look for an embedded raindrop shape, located toward the upper-center of the prementum.

An Ebony Jewelwing damselfly (Calopteryx maculata) exuvia was collected along a small stream located in eastern Fairfax County, Virginia USA.

Family Calopterygidae (Broad-winged Damselflies) | prementum

Family Coenagrionidae (Narrow-winged Damselflies)

The shape of the prementum for Family Coenagrionidae reminds me of a keystone.

A Narrow-winged Damselfly exuvia — probably Argia sp. (it’s a work in progress) — was collected along the Potomac River in Fairfax County, Virginia USA. This individual is a female, as indicated by the rudimentary ovipositor located on the ventral side of her abdomen.

Family Coenagrionidae (Narrow-winged Damselflies) | ventral

The lamellae, also known as caudal lamellae, are external structures used by damselfly larvae for both respiration and locomotion. In contrast, the respiratory system for dragonfly larvae is internal. Characteristics of the caudal lamellae (including shape of/patterns on) are some of the clues that can be used to identify damselflies to the genus/species level.

Family Lestidae (Spreadwings)

The unique shape of the prementum for Family Lestidae reminds me of a rattle (musical instrument).

A damselfly exuvia from the Family Lestidae (Spreadwings) was collected from a small vernal pool located in eastern Fairfax County, Virginia USA. Although the genus/species is unknown (again, it’s a work in progress), both Slender Spreadwing (Lestes rectangularis) adults and Southern Spreadwing (Lestes australis) adults were observed at the vernal pool on the same day this specimen was collected.

Family Lestidae (Spreadwings) | prementum

Related Resources

The first step is the hardest, as the saying goes. In this case, it’s easier to identify damselfly larvae/exuviae to the family level than it is to identify specimens to the genus/species level. There are relatively few resources, especially online resources. The following links to two dichotomous keys and a pattern-matching guide for caudal lamellae should help you get started. Many of the same species of damselflies that are known to occur in Michigan, Florida, and the Carolinas can be found in the mid-Atlantic region.

Copyright © 2017 Walter Sanford. All rights reserved.

American Rubyspot damselfly (male)

January 24, 2017

An American Rubyspot damselfly (Hetaerina americana) was spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male, as indicated by his coloration and hamules.

One and done. That’s the way some wildlife photographers shoot a subject. I like to “work the shot,” that is, shoot the subject from all angles and in different positions.

In this case, the damselfly was perching over deep water. I waded into the water as far as I could go in my knee-high green wellies and made the best of a less than ideal situation.

Since the subject never moved from his perch above the water, I moved so that my viewpoint featured different backgrounds. Also, the damselfly changed position slightly during the shoot. Although all of the photos in this set are similar, each one is different in the way it looks and feels.

Copyright © 2017 Walter Sanford. All rights reserved.

American Rubyspot damselflies

August 21, 2016

American Rubyspot (Hetaerina americana) is a member of the Family Calopterygidae (Broad-winged damselflies). They are common from May to October along rocky streams with riffles, such as the Potomac River at Riverbend Park.

Female

Female American Rubyspots are quite variable in appearance. The following specimen has a metallic green thorax and dark-colored abdomen; its wings feature a color gradient from red at the base to diffuse reddish-orange at the wing tips.

An American Rubyspot damselfly (Hetaerina americana) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | American Rubyspot (female)

The following annotated image illustrates some of the reproductive anatomy of a female American Rubyspot: two cerci (sing. cercus), superior appendages that have little or no function; and two styli (sing. stylus), structures that serve as sensors in egg positioning.

An American Rubyspot damselfly (Hetaerina americana) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a female.

04 AUG 2016 | Riverbend Park | American Rubyspot (female)

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

Male

Male American Rubyspots have a metallic red thorax and dark-colored abdomen; its wings feature well-defined ruby-colored spots at the base. I was so focused on photographing the deep red wing spots that I forgot to shoot a dorsal view of the terminal appendages! No problem. See the digital scans under “Related Resources.”

An American Rubyspot damselfly (Hetaerina americana) spotted along the Potomac River at Riverbend Park, Fairfax County, Virginia USA. This individual is a male.

08 AUG 2016 | Riverbend Park | American Rubyspot (male)

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

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”).

Related Resources:

Copyright © 2016 Walter Sanford. All rights reserved.

Ebony Jewelwing damselflies (male, female)

August 9, 2015

Ebony Jewelwing (Calopteryx maculata) is a member of the Family Calopterygidae (Broad-winged damselflies). They are common from May to July along wooded slow-moving streams such as Dogue Creek in Wickford Park.

Male

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”).

An Ebony Jewelwing damselfly (Calopteryx maculata) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is a male.

05 AUG 2015 | Wickford Park | Ebony Jewelwing (male)

The preceding image also shows the male hamules, …

paired structures that project from pocket under the second segment [S2] and hold female abdomen in place during copulationSource Credit: Glossary [of] Some Dragonfly Terms, by Dennis R. Paulson.

After a male damselfly grabs a female with his claspers, he transfers sperm from the genital opening under the ninth abdominal segment (S9) to his hamules, located beneath the second abdominal segment (S2). Next the pair forms the mating wheel, then the male transfers sperm from his hamules to the female through her genital pore under the eighth abdominal segment (S8).

A mating pair of Ebony Jewelwing damselflies (Calopteryx maculata) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is in wheel (in heart).

06 JUN 2015 | HMP | Ebony Jewelwing (mating pair, in wheel)

The copulatory, or wheel, position is unique to the Odonata, as is the distant separation of the male’s genital opening and copulatory organs. That the position looks as much like a heart as a wheel has been noted. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 377-378). Princeton University Press. Kindle Edition.

Female

A simple field mark may be used to differentiate male and female Ebony Jewelwings: females feature white pterostigmata (see below); males don’t.

An Ebony Jewelwing damselfly (Calopteryx maculata) spotted at Dogue Creek, Wickford Park, Fairfax County, Virginia USA. This individual is an adult female.

05 AUG 2015 | Wickford Park | Ebony Jewelwing (adult female)

The preceding annotated image illustrates some of the reproductive anatomy of a female Ebony Jewelwing: a cercus (pl. cerci), one of two superior appendages that have little or no function; a stylus (pl. styli), one of two structures that serve as sensors in egg positioning; and an ovipositor that is used to insert eggs into submerged vegetation (endophytic oviposition). Notice the mud on the tip of the female’s abdomen, indicating she laid eggs recently.

Copyright © 2015 Walter Sanford. All rights reserved.

Ebony Jewelwing damselfy (female)

August 7, 2011
Img_4079_ver2_aperture_annotatedImg_4079_aperture

An Ebony Jewelwing damselfly (Calopteryx maculata) spotted during a photowalk through “Paul Spring Park,” one of seven small parks owned and maintained by the Community Association of Hollin Hills (CAHH), Fairfax County, Virginia USA. The individual shown in the preceding photo gallery is a female, as indicated by its dull brown body and smoky wings with bright white spots near the wingtips. (Males have metallic green bodies and opaque black wings.)

The Ebony Jewelwing is one of eight species of broad-winged damselflies, a family of medium-size damselflies that have butterfly-like flight. Like all broad-winged damselflies, Ebony Jewelwing damselflies are usually found along small creeks and streams, near the water.

Related Resources:

Tech Tips: Photo 1 of 2 is a copy of the original photograph, cropped to highlight the damselfly; Photo 2 of 2 is the original photograph. Photo 1 was cropped and edge sharpened using Apple “Aperture,” a professional-grade tool for organizing and adjusting photos. Apple “Preview” was used to annotate Photo 1 to highlight the bright white spots near the damselfly’s wingtips.

Ebony Jewelwing damselfies

July 18, 2011
Img_3504Img_3527Img_3529Img_3530Img_3533Img_3545Img_3576Img_3599Img_3458Img_3459Img_3460Img_3467

Several Ebony Jewelwing damselflies (Calopteryx maculata) spotted during a photowalk through the “Wildlife Sanctuary,” one of seven small parks owned and maintained by the Community Association of Hollin Hills (CAHH), Fairfax County, Virginia USA. The individuals shown in the preceding photo gallery are males, as indicated by their metallic green bodies and opaque black wings. (Females have dull brown bodies and smoky wings with bright white spots near their wingtips.)

The Ebony Jewelwing is one of eight species of broad-winged damselflies, a family of medium-size damselflies that have butterfly-like flight. Like all broad-winged damselflies, Ebony Jewelwing damselflies are usually found along small creeks and streams, near the water.

Related Resources:


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