Community identification
Head Louse (Nit)
Pediculus humanus capitis
- Order & Family
- Order: Psocodea (formerly Phthiraptera), Family: Pediculidae
- Size
- Nits (eggs) are 0.8 mm; adults are about 2 to 3 mm long (roughly the size of a sesame seed).
Natural Habitat
The human scalp and hair, specifically within 1/4 inch of the scalp for warmth. They are exclusive parasites of humans.
Diet & Feeding
Strictly blood feeders; they consume small amounts of human blood several times a day by biting the scalp.
Behavior Patterns
They are wingless and cannot jump or fly; they move by crawling. Nits are glued firmly to hair shafts. They undergo incomplete metamorphosis (egg, nymph, adult).
Risks & Benefits
Risks include intense itching (allergic reaction to saliva), sores from scratching, and secondary bacterial skin infections. They do not spread disease. There are no known ecological benefits.