Ebony Jewelwing damselflies (male, female)

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 marker 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.

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