Subject: Stinging Catepillar
Location: 70 km north of Fort McMurray, Alberta
July 30, 2012 11:38 am
I saw this guy in late July in a shrubby area in the boreal forest while working. He was about 2.5-3 inches long with a distinct red stinger. I have no idea what species this is…
Your speculation that because this caterpillar has a horn, it is capable of stinging is incorrect. This is the perfectly harmless caterpillar of the Bedstraw Hawkmoth, a member of the family Sphingidae that has caterpillars commonly called Hornworms. There are several different color variations to the Bedstraw Hawkmoth Caterpillar including black with spots and green with spots as well as your olive drab example. The Bedstraw Hawkmoth Caterpillar feeds on the leaves of Bedstraw in the genus Gallium and Fireweed in the genus Epilobium. You can read more about the Bedstraw Hawkmoth on the Sphingidae of the Americas website.