How do head and pubic lice look? - briefly
«Head lice» are 2–3 mm long, gray‑white, with a flattened, elongated body and six legs ending in tiny claws that cling to hair shafts. «Pubic lice» are 1–2 mm long, broader and darker, resembling a crab with a rounded body and prominent front claws that grasp coarse hair.
How do head and pubic lice look? - in detail
Head lice are tiny, laterally flattened insects measuring 2–4 mm in length. The body is oval, covered with fine hairs that give a gray‑white or light brown appearance. Six legs end in sharply pointed claws adapted for grasping hair shafts. Antennae are short, and the head bears compound eyes positioned laterally. Eggs (nits) are firmly attached to the base of hair strands, appearing as elongated, oval shells about 0.8 mm long, often mistaken for dandruff.
Pubic lice are slightly larger, 1.5–2 mm long, with a broader, crab‑like shape. The body is reddish‑brown to dark brown and densely covered with short, thick setae. Four pairs of legs are equipped with robust claws that cling to coarse body hair. The abdomen is rounded, and the head bears small compound eyes. Nits are smaller than those of head lice, typically 0.5 mm, and are attached near the base of pubic hairs.
Key visual distinctions:
- Size: head lice 2–4 mm; pubic lice 1.5–2 mm.
- Body shape: head lice elongated and flattened; pubic lice broader and crab‑like.
- Leg arrangement: head lice have six legs of equal length; pubic lice have four front legs longer than the rear pair.
- Color: head lice gray‑white to light brown; pubic lice reddish‑brown to dark brown.
- Egg placement: head lice nits on scalp hair shafts; pubic lice nits on coarse body hair, often near the skin surface.
Scientific names are presented as «Pediculus humanus capitis» for head lice and «Pthirus pubis» for pubic lice. Their morphology reflects adaptation to specific host hair types, enabling reliable identification based on the characteristics above.