How many developmental stages does a bedbug have? - briefly
Bedbugs pass through five distinct developmental stages: an egg followed by four successive nymphal instars, after which they become mature adults. Each nymphal stage requires a blood meal before molting to the next.
How many developmental stages does a bedbug have? - in detail
The bedbug life cycle consists of seven distinct phases: an egg, five successive nymphal instars, and the mature adult. Each phase is separated by a molt, during which the insect sheds its exoskeleton to accommodate growth.
The egg stage lasts 6–10 days at typical indoor temperatures (22–26 °C). Eggs are deposited in clusters within cracks and crevices, each encased in a protective shell. After hatching, the first instar nymph emerges, measuring roughly 1.5 mm and lacking fully developed wings.
Nymphal development proceeds through five instars, each requiring a blood meal before molting to the next stage. The duration of each instar varies with temperature and host availability:
- First instar – 5–7 days; requires one blood meal; limited mobility.
- Second instar – 5–10 days; slight increase in size to about 2 mm; second blood meal needed.
- Third instar – 7–14 days; body length reaches ~2.5 mm; third blood meal required.
- Fourth instar – 10–14 days; size approaches 3 mm; fourth blood meal needed.
- Fifth instar – 12–21 days; final nymphal size about 4 mm; fifth blood meal precedes adulthood.
After the fifth molt, the insect attains the adult form, characterized by fully developed wings (non‑functional for flight), a length of 4.5–5 mm, and reproductive capability. Adult longevity ranges from several months to over a year, depending on environmental conditions and access to blood meals.
In summary, the developmental sequence comprises one egg, five progressive nymphal stages, and the adult, each stage defined by specific morphological changes and obligatory blood meals. The scientific name of the common bedbug is «Cimex lectularius».