How do lice look on adult hair? - briefly
Adult head lice measure 2–4 mm, appear gray‑white, flat, and have six legs ending in claw‑like hooks that grip hair shafts. They are seen as tiny moving specks near the scalp, especially around the hair line and behind the ears.
How do lice look on adult hair? - in detail
Lice that infest fully grown human hair are small, wing‑less insects measuring 2–4 mm in length. Their bodies are flattened laterally, allowing them to move easily between strands. The exoskeleton is a pale gray‑white or tan color, often appearing translucent when the insect is unfed; after blood meals the abdomen becomes darker, sometimes reddish‑brown.
The head is rounded with short antennae that protrude just beyond the body’s outline. Eyes consist of simple ocelli, visible as tiny dark dots near the front of the head. Mouthparts are adapted for piercing skin and sucking blood; they are not externally prominent but can be inferred from the slightly enlarged, bulbous abdomen of a fed specimen.
Legs are six in number, each ending in a claw that grips hair shafts securely. The claws are visible as tiny, curved structures at the tip of each leg, enabling the parasite to cling to the hair’s surface and to the scalp’s skin.
Eggs (nits) are oval, 0.8 mm long, and adhere firmly to the hair shaft near the scalp. They are typically yellow‑white, turning tan or brown as they develop. The nit’s attachment point is a cement‑like substance that resists removal by regular combing.
Key visual cues for identification:
- Size: 2–4 mm, visible to the naked eye.
- Color: pale gray‑white when unfed; darker after feeding.
- Body shape: flattened, elongated, with a visible head and six legs.
- Claws: small, hooked at the end of each leg.
- Nits: oval, attached close to the scalp, cemented to the hair shaft.
These characteristics enable reliable detection of the parasite on adult hair without the need for magnification, though a fine‑tooth comb or handheld lens can improve accuracy.