Harpaphe

Harpaphe is a small genus of 7 accepted species, with Harpaphe haydeniana having two subspecies: H. haydeniana inlignea and H. haydeniana haydeniana, which are both endemic to the upper western coast of North America. Reports from citizen scientists shows the greatest density and diversity of H. haydeniana extending from the western coast of Oregon, up through Seattle, Washington, into Vancouver in British Columbia, and the Vancouver Islands, though this is likely more the result of a sampling bias than actually pointing to more specimens being found near large cities (1).

Care information on this genus is limited, and the few reports of captive specimens usually end with the specimens slowly expiring, which is exacerbated by temperatures above 72°F/22.2°C.
One contributor has regularly observed Harpaphe haydeniana in British Columbia, and notes that the defensive secretions smell like roasted almonds. She also observed what is believed to be an H. haydeniana that had a base caramel color with white spots in contrast to the normal black base with yellow spots of the species, but it has not yet been ascertained whether the specimen is truly a color variant, a large juvenile, or another species altogether.

Harpaphe haydeniana has a base color of black with bright yellow-tipped paranota, brownish-black legs and antenna, and grows to about 40 mm (1.57"/4 cm) (2).
John S. Buckett and Michael R. Gardner noted in a 1968 paper that the similar H. telodonta reached to 33mm (1.3"/3.3 cm), with the first five segments broadenening from 3.5mm to 4.5 mm quite noticeably out to segment 17.
The majority of the Harpaphe in the Pacific Northwest cannot be told apart from each other except on the basis of locality and gonopod dissection (3).

  1. iNaturalist. (2021). Genus Harpaphe. Map. https://www.inaturalist.org/taxa/47738-Harpaphe

  2. Buckett, J. S., & Gardner, M. R. (1968). Rediscovery of the Type of the Milliped, Harpaphe telodonta (Chamberlin) (Diplopoda: Eurydesmidae). Journal of the New York Entomological Society, 76(1), 60–63. http://www.jstor.org/stable/25006091

  3. BugGuide. (2021). Species Harpaphe haydeniana. Accessed at: https://bugguide.net/node/view/15008 on 2021-12-20

  4. Sierwald, P.; Spelda, J. (2013). MilliBase. Harpaphe Cook, 1904. Accessed at: http://www.millibase.org/aphia.php?p=taxdetails&id=891700 on 2021-11-10