Yellow-spotted Millipede - Harpaphe haydeniana

Harpaphe haydeniana haydeniana (Wood)

This photo is indeed of the nominate subspecies of Harpaphe haydeniana, the dominant Pacific Coastal representative of the Xystodesmidae (=Eurydesmidae) from northern California to southern Alaska. It belongs to a different "tribe" (a taxonomic category below family but above genus) from the xystodesmids in eastern North America, and the body proportions are noticeably different; it is narrower for its length than the species of Apheloria, etc.

… Rowland Shelley, 5 March, 2007 - 8:00pm

Cyanide secreting

My understanding is that this is one of those millipedes that secretes cyanide compounds to defend itself, so please be careful handling them.

… Eric R. Eaton, 8 February, 2005 - 10:57am

I can vouch for that

I was only 8 or so, and after handling one I rubbed my eye. Big mistake. It burned like heck, and I couldn't open my eye to see out of it for several hours. The next day there was a tiny scab on the top of my eyelid. I later read about the cyanide compounds, and you can certainly smell them by rubbing one of these guys with a stick. Smells like almond extract.

… Richard C. Hoyer, 12 June, 2006 - 4:25pm