Gonopods
Guides
Aniulus
Aniulus is a genus of North American millipedes in the family Parajulidae, comprising at least 20 described species. The genus belongs to the order Julida, characterized by cylindrical bodies and typically inhabiting forest floor habitats. Detailed behavioral studies exist for at least one species, Aniulus bollmani, documenting complex courtship and mating behaviors.
Callipodida
Crested Millipedes
Callipodida is an order of millipedes comprising approximately 130 species across three extant suborders and seven families. Members are characterized by elongated bodies with 40–60 segments, reaching up to 100 mm in length, and often display distinctive dorsal crests or ridges. The order exhibits a disjunct distribution across the Northern Hemisphere, with populations in North America, Europe, western Asia, southern China, and Southeast Asia. Sexual maturity is achieved through teloanamorphosis, with males possessing a single pair of gonopods derived from the seventh leg pair.
Harpaphe haydeniana
yellow-spotted millipede, almond-scented millipede, cyanide millipede
Harpaphe haydeniana is a flat-backed millipede native to the Pacific coast of North America, recognized by its black body with yellow-tipped lateral keels. The species is notable for its chemical defense system, secreting hydrogen cyanide when threatened, which produces a characteristic almond odor. It plays a significant role in forest decomposition, particularly in redwood ecosystems. Despite its common names suggesting uniqueness, both the color pattern and cyanide defense occur in other flat-backed millipedes globally.