Community identification
Human Head Louse (Egg or Nymph stage)
Pediculus humanus capitis
- Order & Family
- Order: Psocodea (formerly Phthiraptera), Family: Pediculidae
- Size
- Nymphs are 1-2 mm, adults are 2-3 mm (roughly the size of a sesame seed). Eggs (nits) are approximately 0.8 mm.
Natural Habitat
Exclusively found on the human scalp and hair, where they stay close to the skin for warmth and food.
Diet & Feeding
Obligate hematophages; they feed exclusively on human blood several times a day.
Behavior Patterns
They cannot fly or jump, moving only by crawling. Females glue eggs (nits) to hair shafts near the scalp. They spread primarily through direct head-to-head contact.
Risks & Benefits
Risks include intense itching (pruritus), sleep loss, and secondary bacterial skin infections from scratching. They are not known to transmit systemic diseases. There are no ecological benefits to humans.