Archive | 12:00 pm

Water to Air – Baby Dragonflies

25 Feb
Final instar nymph of an aeshnid dragonfly.

Final instar nymph of an aeshnid dragonfly (College Station, TX).

Two years running our first planned field outing for the spring has coincided with one of Texas’s rare dips into below freezing weather.  While fishing around in lakes is not the ideal pasttime for this kind of temperature, it is a decent way to get hold of some insects even in cold weather.  One group of insects that’s a relatively common find are the aquatic immatures of dragonflies and damselflies.  The dragonfly nymphs in particular are striking little creatures, with the earlier instars resembling squat little brown frogs.  Like their adult incarnation, they’re also impressive predators, even tackling small fish.

Early and late instar dragonfly nymphs (Libellulidae).

Early and late instar dragonfly nymphs (Libellulidae, Aeshnidae).

Dragonflies lack a pupal stage, so the developing wings (wing pads or wing buds) can be seen in the late immature instars.  I hadn’t caught a final instar dragonfly nymph before, so I was suitably excited to see one up close.  The larger fellow above even obliged us by molting into a pretty blue darner during the middle of a lecture on dragonfly metamorphosis to a group of introductory entomology students.

*edit* Thanks to Jim Johnson for family corrections and additional information about nymphal characters.