Pubic louse (Crab louse)
Scientific Name: Pthirus pubis
Order & Family: Order: Psocodea (formerly Anoplura), Family: Pthiridae
Size: 1.1 mm to 1.8 mm (about the size of a pinhead)
Natural Habitat
Coarse human body hair, primarily in the pubic region, but occasionally eyelashes, beard, or chest hair.
Diet & Feeding
Obligate hematophage; they feed exclusively on human blood several times a day.
Behavior Patterns
They are relatively immobile and grasp hair shafts using specialized claw-like legs. They cannot jump or fly and generally spread through close physical contact.
Risks & Benefits
Risks include intense itching (pruritus) due to hypersensitivity to saliva, and secondary bacterial infections from scratching. They are not known to transmit systemic diseases.
Identified on: 5/21/2026