How does a newly hatched louse look? - briefly
A newly emerged louse is a tiny, translucent, pale oval nymph roughly 0.5 mm in length, lacking the dark pigmentation of mature insects. It is almost invisible against hair shafts.
How does a newly hatched louse look? - in detail
A newly emerged louse measures approximately 1 mm in length, slightly shorter than an adult. Its body is elongated, flattened laterally, and covered with fine, translucent cuticle that allows underlying internal structures to be faintly visible. The coloration ranges from pale yellow‑white to a faint brown, depending on the amount of hemoglobin absorbed from the host’s blood.
The head region is small, bearing a pair of short antennae that extend only a fraction of a millimeter. Mouthparts are already formed as piercing‑sucking stylets, though they appear less robust than in mature individuals. Compound eyes are present but appear as tiny, indistinct spots on the dorsal surface.
The thorax consists of three distinct segments, each bearing a pair of legs. Legs are slender, ending in claw‑like tarsi adapted for grasping hair shafts. At this stage, the legs lack the thickened, hardened exoskeleton seen in adults, making them more delicate and translucent.
The abdomen contains eight visible segments. Early nymphs possess unsegmented, unpigmented internal organs, and the terminal segment bears a small, underdeveloped anal opening. Spiracles for respiration are present on the lateral sides of the posterior abdominal segments, appearing as minute openings.
Key visual characteristics:
- Length: ~1 mm, slightly shorter than adult stage.
- Color: pale yellow‑white to faint brown, translucent cuticle.
- Head: tiny antennae, rudimentary piercing‑sucking mouthparts, faint eye spots.
- Legs: six slender legs with clawed tarsi, delicate exoskeleton.
- Abdomen: eight visible segments, underdeveloped anal opening, lateral spiracles.
These attributes collectively define the appearance of a freshly hatched louse before it undergoes the successive molts that lead to the fully pigmented, larger adult form.