Subject: Unknown Butterfly Larvae
Location: Upstate New York
August 8, 2012 1:21 pm
It’s been around high seventies to eighties (Fahrenheit) up here for the past few days…this little one is about 4 inches long, and moves rather slowly. We found it on a concrete slab, and have no idea what it could be. All help would be appreciated, so we know what to feed the little fellow.*9
Thanks to your submission, we have learned an interesting bit of information. We like to be able to cite sources when we provide responses, and rather than to just inform you that this is the caterpillar of an Imperial Moth, we turned to BugGuide where we learned that this is a subspecies known as the Pine Imperial Moth, Eacles imperialis pini. Here is how BugGuide differentiates the caterpillars of the two subspecies: “Larva [Eacles imperialis pini]: abdominal segments have two rows (dorsal and dorsolateral) of large shiny white scoli (fleshy protuberances); spiracles white” while “nominate subspecies imperialis larva is larger (95-115 mm), dorsal and dorsolateral scoli much smaller or lacking, and spiracles usually yellow.” BugGuide also indicates: “larvae feed exclusively on conifers, mainly White Pine and Red Pine; also recorded on Jack Pine, Scotch Pine, and White Spruce” and based on the size and dark coloration of your individual, we suspect it has left its food source and is preparing to metamorphose into the pupal stage. The caterpillar digs into the dirt when it is ready to pupate and the pupa is naked, not wrapped in a silken cocoon. We don’t believe your caterpillar will be interested in eating since it is most likely preparing for pupation. You can get additional information on Bill Oehlke’s Silkmoths website.