In the “middle of winter” this reader finds “short, small, black worms by the hundreds in [his] driveway […] trying to get into the house.” He states that no one seems to know what these segmented, black larvae-looking critters are, and he hopes that the picture he has attached helps.

We can assure our reader that the picture definitely helps, as it always helps to have photographic information on the worms we attempt to identify.

From looking at the uneven, shallow segmentation on these creatures’ bodies, their coloration, and way in which they are moving, we would suppose that these might be intermediate hooded owlet moth caterpillars.

This might be the one case in which it is easier, if not faster, to say their Latin name: Cuculia intermedia, meanwhile their English name provides a rather entertaining tongue twister.

The adult moth of the Cuculia intermedia is a large, gray, furry moth with a wingspan of up to 2-inches. They are found pretty much all over The United States, but are primarily found in the Eastern and Midwestern States, as well as in central Canada.

Unfortunately, not much is known about the behavior of Cuculia intermedia and their caterpillars. The moths will take flight and migrate from May to August, and depending on how long the caterpillars stay at this stage before pupation, it could make sense that there are roaming caterpillars in the middle of winter.

The only thing that puts a hole in this theory is that the caterpillars feed on lettuce plants, which could only be grown in certain conditions during the middle of winter. That said, we do not know that our reader is not harvesting lettuce in his garden or home, so if this is the truth of the matter, then this may be why these caterpillars showed up on our reader’s driveway.

Otherwise, it is a mystery why so many of them have gathered on his doorstep, waiting to be let in. It could also be that they are not intermediate hooded owlet moth caterpillars after all.

What we recommend that our reader do is put a couple of these creatures in a container with some air holes and some food (definitely put lettuce inside, as well as leaves and stems from other plants). Then he can track the caterpillars’ growth, as well as keep an eye out for what they prefer to eat, and a more certain identification can be made at a later time.

Perhaps they will even make it through pupation and into moth-hood, at which point it would be even easier to reach a conclusion on their identity. With regard to the hundreds of other caterpillars on his driveway, we suggest simply shoveling them up (gently) and moving them elsewhere (preferably somewhere vegetated).

To conclude, the small black worms our reader found by the hundreds on his driveway may be intermediate hooded owlet moth caterpillars (Cuculia intermedia), though we are not certain. There is so little literature on this caterpillar, so we cannot even confirm or deny whether or not they travel in groups as large as these. As we said, we welcome our reader to try raising a couple of the caterpillars and see what happens. He can then come back to us later with more photos and information and we can have another go at identifying them. We wish him the very best!

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