What do flea eggs and larvae look like? - briefly
Flea eggs are minute, oval, about 0.5 mm in length, smooth, and appear white to off‑white. Once hatched, the larvae are slender, worm‑like, 2–5 mm long, cream‑colored with a dark head capsule and lacking legs.
What do flea eggs and larvae look like? - in detail
Flea eggs are minute, oval structures measuring approximately 0.5 mm in length and 0.2 mm in width. Their shells are smooth, translucent to off‑white, and lack any discernible ridges. When freshly laid, they appear slightly glossy; after a few hours, the surface becomes dull as the outer membrane absorbs moisture. Eggs are typically deposited in clusters of 20–30 on the host’s bedding, carpet fibers, or cracks in flooring, where they remain hidden from direct observation.
The first larval stage emerges after 2–5 days of incubation, depending on temperature and humidity. Newly hatched larvae are slender, C‑shaped grubs about 1–2 mm long. Their bodies consist of three distinct regions: a hardened head capsule, a soft thoracic segment, and a tapered abdomen. The cuticle is creamy‑white, often covered with fine, hair‑like setae that aid in movement through debris. Each larva possesses a pair of short, chewing mandibles used to consume organic detritus, including adult flea feces (which contain blood).
During the second instar, which lasts 3–5 days, the larva increases to 3–4 mm. The body becomes more robust, the head capsule darkens to a light brown, and the setae become more pronounced. The abdomen expands, allowing storage of food before pupation. The third instar, lasting another 4–6 days, reaches 5–6 mm in length. Its cuticle thickens, taking on a slightly yellowish hue. The mandibles remain functional, and the larva continues to feed on detritus and adult flea excrement, accumulating enough energy reserves for metamorphosis.
Pupal cocoons are formed when the fully grown larva spins a silken sac within a protected crevice. The cocoon is brownish, irregularly shaped, and may contain a small amount of debris for camouflage. Inside, the pupa appears as a compact, whitish mass that gradually darkens as the adult flea develops.
Key visual cues for identification:
- Eggs: oval, 0.5 mm, translucent, smooth surface.
- First‑instar larvae: 1–2 mm, C‑shaped, creamy‑white, fine setae, visible mandibles.
- Second‑instar larvae: 3–4 mm, thicker body, light brown head capsule, longer setae.
- Third‑instar larvae: 5–6 mm, yellowish cuticle, robust mandibles.
- Pupae: brown silken cocoon, compact whitish interior that darkens over time.
These characteristics enable accurate recognition of each developmental stage in a domestic environment.