Flat-backed Millipede

Scientific Name: Polydesmida

Order & Family: Order Polydesmida, Families vary (e.g., Paradoxosomatidae or Polydesmidae)

Size: Typically 10mm to 40mm in length, depending on the species.

Flat-backed Millipede

Natural Habitat

Damp leaf litter, rotting logs, soil, and gardens with high organic matter.

Diet & Feeding

Detritivores; they primarily feed on decaying plant matter, fungi, and organic debris in the soil.

Behavior Patterns

Slow-moving and nocturnal. They lack eyes and use antennae to navigate. Many species can secrete defensive chemicals (like hydrogen cyanide) from glands on their sides when threatened.

Risks & Benefits

Benefits: Essential decomposers that help cycle nutrients back into the soil. Risks: Harmless to humans, though some species may secrete a liquid that can irritate the skin or eyes; they are occasionally minor garden pests if they feed on tender seedlings.

Identified on: 2/19/2026