For those species of dragonflies that do not display sexual dimorphism, males and females are nearly identical in appearance except for their terminal appendages. For example, male and female Cobra Clubtail dragonflies (Gomphurus vastus) are similar in appearance.
Two field marks can be used to identify female Cobra Clubtails, as shown in the following annotated images: 1) they have two terminal appendages (cerci) rather than three (males); and 2) their hind wings are rounded rather than “indented” (males).
16 MAY 2016 | Riverbend Park | Cobra Clubtail (female)
(See a full-size version of the original photo, without annotation.)
All female dragonflies have a pair of cerci (superior appendages) that have little or no function.
16 MAY 2016 | Riverbend Park | Cobra Clubtail (female)
(See a full-size version of the original photo, without annotation.)
Related Resource: Cobra Clubtail claspers [males], by Walter Sanford.
Copyright © 2016 Walter Sanford. All rights reserved.
Tags: cerci, Clubtail Family, Cobra Clubtail dragonfly, female, Gomphurus vastus, Riverbend Park, terminal appendages, wildlife photography
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