Crab Louse (also known as Pubic Louse)

Natural Habitat

Exclusively inhabits coarse human hair, most commonly in the pubic region, but can occasionally be found in eyelashes, eyebrows, beard hair, and armpits. They cling to hair shafts near the skin.

Diet & Feeding

Hematophagous (feeds exclusively on human blood).

Behavior Patterns

These parasitic insects are relatively sedentary, using their large, crab-like claws to tightly grip hair strands. They complete their entire life cycle (egg, nymph, adult) on the human host and require frequent blood meals to survive.

Risks & Benefits

Risks: An infestation (pediculosis pubis) causes intense itching and skin irritation due to an allergic reaction to the louse's saliva. Scratching can lead to secondary bacterial skin infections. While nuisance pests, they are not currently known to transmit disease.

Identified on: 2/22/2026