Wake Audubon Blog

Imperial Moth – Look for larvae in autumn

i Oct 10th 1 Comment by

Imperial Moth authored by John Gerwin

This evening I nearly stepped on the dark larva pictured below. Glad I didn’t, as I might have twisted an ankle!  This is the caterpillar of an Imperial Moth. A few years ago, in early August, I found a recently emerged adult in our front yard, and I’ve attached a couple images of that. It’s a lovely form indeed. Depending on the light, the darker color varies in intensity but always seems to be some form of violet.  I believe this is a male, with so much violet.

The larva apparently comes in two flavors, and both are shown here. The green guy we found at Durant Park last year in late September.  Larva seem to be most common in September/October. I’m used to thinking of a “brown” form of caterpillar like this as a “pre-pupal” stage. This species pupates in the soil and I presume it was crawling across the parking lot to find some suitable soil. Instead, it now finds itself in a garden plot of ours out back!  (with nice loose, loamy soil and plenty of soft dead leaves).

On the latter few dark form images, the flash highlights the animals colors more than what we could see in the kitchen light. When we found it, it was already getting dark outside, so I don’t know what “natural light” would show – it’s dark to be sure but the greenish cast is there. The spiny knobs were definitely visible in any light. When it extended itself on the kitchen counter it was 5+ inches in length.

IN 1909 naturalist/author Gene Stratton Porter wrote a novel entitled “The Girl of the Limberlost”. Porter was considered one the most popular female novelists of that era – by the time of her death in 1924, 10 million copies of her various books had been sold. In the above mentioned novel, Elnora is a young (nerdy?) woman with a penchant for nature study.  Growing up fatherless and mostly alone in a poor rural Indiana setting, one thing she does is learn to collect and sell nature objects, including moths. I have not read the novel but apparently the Imperial Moth is prominently featured……….

A real treat!