Dragonfly or Damselfly?Side by Side The Little and Large Show The Shell Game Going to Extremes Side by Side answer Going Zen The Rule Acknowledgement of sources
Author Jeff Melvaine ◦
Many people, when asked “What’s the difference between a dragonfly and a damselfly”, would probably remember reading / hearing something like this, or part of it:
| Characteristic | Dragonfly | Damselfly |
|---|---|---|
| Wings when perched | Open | Closed |
| Eye separation * | Meeting | Widely spaced |
| Build | Robust | Slender |
| Size | Medium to large | Small to medium |
| Forewing and hind wing structures | Different | Similar |
| Flight | Strong, fast | Weak, slow |
| Larvae (“mud eyes”) breathe underwater using | Internal gills | External gills |
This page is here to explore why the above generalisations are often true, and how they can be surprisingly misleading in some cases. I’ll focus mainly on my area of personal experience, Australia (which lives up to its reputation for producing weird endemics like the duck-billed platypus and the kangaroo paw, even when the focus is on insects), but some exceptional overseas species that have come to my attention help to illustrate the diversity of the subject matter. It’s not a short story, but I’ll make liberal use of pictures and put a TLDR summary at the end of each major section for those who prefer to skim. I am not assuming that readers already know a lot about the biology of these insects, and some of the details get quite technical.
Some of you may be wondering “is a damselfly a kind of dragonfly, or are they different?” The short answer is “yes and yes” in everyday casual usage, but to avoid confusion, I will avoid the term “true” dragonflies and use “Odonate” as the all-inclusive term (from Odonata, the scientific name, meaning “things with big scary teeth”, or more literally “toothed”). That group is called an order; it contains the suborders Zygoptera (“twin wings”) for the damselflies, and Anisoptera (“different wings”) for the dragonflies. To be clear, I will speak of Odonate wings being closed rather than folded; beetles fold their large hindwings by bending the wing surface along natural crease lines in order to pack them away under the smaller hardened forewings, but no Odonate does that. And although many people (including myself) know Odonates much better as winged adults than as water-dependent larvae or “mud eyes” (I’ll be talking about the adults unless otherwise stated), the larval stage of the Odonate life cycle is relevant to the discussion; it strongly influences what Odonates can become as adults.
Dragonfly or Damselfly?Side by Side The Little and Large Show The Shell Game Going to Extremes Side by Side answer Going Zen The Rule Acknowledgement of sources
Footnote & References
- Author Jeff Melvaine / Photographs © Jeff Melvaine
Dragonflies & DamselfliesDragonfly or Damselfly? Sex Lives and Dragonflies Damselflies Diplacodes haematodes Hemicordulia tau Orthetrum caledonicum Orthetrum migratum Orthetrum villosovittatum
InsectsBees Beetles Blattodea Butterflies Coleoptera Cicada Crabronidae Diptera Dragonflies & Damselflies Formicidae Hemiptera Heteroptera (True Bugs) Mango Planthopper Moths Orthoptera Orthopteroid Processionary Caterpillar Stink Bugs, Shield Bugs and Allies Syrphidae Wasps Water Scorpion (Laccotrephes tristis) Witchetty Grub