…one’s first impression might be that this creature has somehow lost its way out of an Amazonian jungle.

~David L. Wagner, describing the Crowned Slug caterpillar in Caterpillars of Eastern North America

When I returned from our California trip, I looked around the yard and saw what lies ahead – lots of yard work. Seems as though autumn had arrived while we were away – leaves changing colors and dropping, branches and twigs littering the ground, and an accumulation of acorns on the back deck. This is apparently a good year for the mast crop (acorns and hickory nuts). So, I began by sweeping off the walkway and deck.

Cleaning up the acorns on the deck (click photos to enlarge)

The two large oaks out back drop an impressive number of acorns every few years (usually with a resounding clang on the metal roof and deck). I swept up almost a 5-gallon bucket of nuts that had fallen in a week and a half.

Crowned Slug caterpillar

As I finished sweeping up, I noticed a splash of color on one of the fallen oak leaves – a caterpillar. And not just any caterpillar, one of my favorites, the Crowned Slug (Isa textula). This is one of the more bizarre-looking of the “stinging” caterpillars.

Close up of stinging spines

This unusual species is characterized by a series of lobes projecting from the sides of the body, each lobe containing an array of long, stinging spines. Additional stinging spines are found in clusters near the middle of the dorsal surface. The head region is marked by two elongate projections edged in red.

Crowned Slug feeding on dried oak leaf

I was initially surprised to find one so late in the season, and to see it feeding on an obviously dry fallen leaf. But when I looked it up in Caterpillars of Eastern North America, the author said these caterpillars may be active very late in the season, sometimes dropping down with autumn rains and wind. So, I guess it is not so unusual after all.

A beautiful way to finish another great caterpillar season

After spending a few minutes photographing it, I placed this late larva on a fresh oak leaf out back. If this is the last larva of the season, it is a memorable one…slug royalty. I’m already looking forward to next year…