How does a tick larva differ from a nymph? - briefly
A tick larva has six legs and is unfed, whereas a nymph has eight legs and has already taken at least one blood meal.
How does a tick larva differ from a nymph? - in detail
Ticks undergo several developmental stages before reaching adulthood. The earliest free‑living stage is the six‑legged larva, which follows the egg. After a blood meal, the larva molts into the eight‑legged nymph, which then feeds again before molting into the adult.
Key distinctions:
- Leg count: Larvae possess three pairs of legs; nymphs have four pairs.
- Size: Larvae measure 0.5–1.0 mm when unfed; nymphs range from 1.0–2.5 mm.
- Feeding duration: Larval attachment lasts 1–3 days; nymphal feeding extends 3–7 days.
- Host selection: Larvae typically attach to small mammals, birds, or reptiles; nymphs can infest larger mammals, including humans.
- Pathogen acquisition: Larvae rarely carry disease agents because they have not yet fed; nymphs often acquire and transmit pathogens after their first blood meal.
- Morphology: Nymphs develop a more pronounced scutum and larger capitulum, reflecting increased mouthpart size for deeper tissue penetration.
- Molting cycle: After feeding, larvae molt to nymphs within 7–10 days; nymphs molt to adults after a second feeding period of 10–14 days.
These differences influence each stage’s ecological role, host interactions, and relevance to disease transmission.