By now, it should not come as much of a surprise that I go to gardens to look for insects more than to look at the plants themselves. The wide variety of plants in gardens attracts a diversity of insects, especially when the gardeners prioritize native plants (and refrain from spraying pesticides all over). On this particular garden trip, I started out by looking for plants with leaf damage and soon came across a patch of plants that appeared to have been hosting a feast. However, standing above the plants, I did not see any of the feasters; were they still there? Spotting some frass (insect droppings) on one leaf, I crouched down to inspect the overhanging leaf.
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| A larva on the underside of a leaf with some frass below. |
I had expected to see a caterpillar and what I found was caterpillar-like, but its spiral pose instantly made me suspicious. When I flipped the leaf over to get a better look and saw its eyes, my suspicion that it was not a caterpillar was confirmed. (If it had been a caterpillar, I should not have been able to see its real eyes.) Instead, it was a sawfly -- a relative of wasps and bees.
Once I had found the first one, it became easier to find even more of the sawfly larvae. From one of these that wasn't curled up, I could see another distinctive difference: the larva had too many legs to be a caterpillar. (Caterpillars have five or fewer fleshy "prolegs" after the first three jointed, true legs; sawfly larvae have six or more prolegs.)
Recognizing the larvae as sawflies was an important step towards identifying their species.
Identifying their host plant would expedite the rest of the task. Luckily, identifying this host plant as white turtlehead (
Chelone glabra) only required some simple inference.
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| There was no need to work through a key to identify this plant! |
Explore some more:
Wild Gardens of Acadia and
Lepidopteran vs Sawfly Larvae
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