Pubic Louse (Crab Louse)

Natural Habitat

Exclusively found on humans, primarily in the pubic hair and surrounding groin area, but can occasionally inhabit armpits, beards, eyelashes, or eyebrows.

Diet & Feeding

Obligate hematophage; they feed exclusively on human blood several times a day.

Behavior Patterns

They are sedentary and move slowly. They use their specialized crab-like claws to grasp thick hair shafts and remain glued to the host. They undergo hemimetabolous metamorphosis: egg (nit), nymph, and adult.

Risks & Benefits

Risks include intense itching (pruritus) due to an allergic reaction to their saliva, and small blue spots on the skin from feeding. They are not known to transmit diseases but are primarily spread through close physical/sexual contact or infested bed linens/clothing.

Identified on: 3/7/2026