Dragonfly Nymph Shed Skin – More elongated than usual
Here’s a shed skin from a dragonfly nymph that Sandy and Rosie found while they were out fishing. This one has a longer, thinner abdomen than dragonfly nymph molts that we’ve found previously.
Some poking around on BugGuide suggests that the more-elongated nymphs are likely to be Darners in the family Aeshnidae, which are some of the dragonflies with extremely long, narrow abdomens as adults. It also looked like identifying it more closely than this would have required seeing the adult.
I was particularly interested in trying to get better pictures of the extensible lip that these nymphs use to catch prey. You can see it folded up underneath the head.
This shoots out forward so that the nymph can grab prey as it swims by, without the nymph actually having to move its body through the water. This allows it to catch things that swim much faster than the nymph can.
The “grabbers” at the end of the lip are pretty distinct here. They are multi-pronged, and look like they would hold onto small prey items pretty securely. Even though these look a lot like standard insect mandibles, they are not. The actual mandibles that the nymph uses to chew up food are hidden underneath. The grabbers are actually derived from one of the pairs of “palps” that insects have around their mouths to aid in food handling.
I had hoped to be able to extend the lip, but the molt was too dry and fragile, and the head popped off instead. Although, this did make it easier to get a clear view of the folded lip, at least.
Someday, I’ll manage to get a picture of a nymph with the lip extended, I’ll just have to keep trying.
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