Pubic louse (Crab louse)
Scientific Name: Pthirus pubis
Order & Family: Order: Psocodea (formerly Anoplura), Family: Pthiridae
Size: 1.1 mm to 1.8 mm (roughly the size of a pinhead or freckle)
Natural Habitat
The coarse hair of the human body, most commonly in the pubic area; also found in eyelashes, eyebrows, beard, and chest hair.
Diet & Feeding
Obligate ectoparasite; feeds exclusively on human blood by piercing the skin.
Behavior Patterns
They are slow-moving and cling tightly to hair shafts with specialized crab-like claws. They cannot jump or fly and are usually transmitted through close physical contact or shared bedding.
Risks & Benefits
Risks include intense itching (pruritus) due to an allergic reaction to their saliva and potential secondary skin infections from scratching. They are not known to transmit diseases.
Identified on: 1/14/2026