How do hair‑eating lice look? - briefly
Hair‑eating lice are tiny, wingless insects about 1–2 mm long, possessing a flattened, elongated body that ranges from tan to translucent and six clawed legs adapted for gripping hair shafts. Nymphs look alike but are marginally smaller and lighter in color.
How do hair‑eating lice look? - in detail
Hair‑consuming lice are small, wingless insects with a flattened, oval body measuring 0.8–3 mm in length. The exoskeleton is semi‑transparent, allowing internal organs to be faintly visible; coloration ranges from pale ivory in nymphs to light brown or reddish‑brown in mature specimens. Six short, grasping legs end in claw‑like tarsi that cling tightly to individual hair shafts. The head bears a pair of antennae, each consisting of five segmented filaments, and compound eyes positioned laterally.
The abdomen consists of seven visible segments, each bearing fine bristles (setae) that aid in sensory perception and movement through hair. In adult females, the abdomen expands to accommodate egg production, giving a slightly rounded silhouette compared with the more slender male. Eggs (nits) are oval, 0.5 mm long, and adhere to the hair shaft with a cement‑like secretion, typically found within 1 cm of the scalp. Nits appear ivory when freshly laid and darken to gray or black as the embryo develops.
Key visual distinctions:
- Size: Nymphs 0.8–1.2 mm; adults 1.5–3 mm.
- Color: Nymphs pale; adults light brown to reddish‑brown.
- Body shape: Flattened, oval; females slightly broader abdomen.
- Legs: Six short, clawed legs adapted for gripping hair.
- Antennae: Five‑segmented, protruding laterally.
- Eggs: Oval, 0.5 mm, cemented close to the scalp, color shifts from ivory to gray/black.
When observed under a magnifying lens, the lice’s dorsal surface appears smooth, while the ventral side shows a series of tiny, evenly spaced setae. The mouthparts are concealed beneath the head capsule, specialized for piercing hair follicles and extracting keratinous material. These characteristics collectively enable reliable identification of hair‑feeding lice in clinical or forensic examinations.