What do flea larvae and pupae look? - briefly
Flea larvae are tiny, whitish, worm‑like organisms about 2–5 mm long, covered in fine hairs and lacking legs. Pupae develop inside an oval, dark brown to sand‑colored protective case roughly the size of an adult flea.
What do flea larvae and pupae look? - in detail
Flea larvae are slender, whitish organisms measuring 2–5 mm in length. Their bodies consist of three distinct sections: a head capsule, a thorax with three pairs of short, claw‑like legs, and an elongated abdomen. The cuticle is soft and lacks sclerotization, giving the larvae a translucent appearance that reveals internal organs. They possess no eyes or antennae; instead, they rely on sensory hairs (setae) distributed along the sides to detect vibrations and chemical cues. The abdomen bears numerous fine bristles that aid in movement through the moist, organic debris of the host’s environment.
Pupal development occurs within a protective cocoon, often termed a “flea cocoon” or “pupal case.” The cocoon is oval, slightly flattened, and measures roughly 3–6 mm in diameter. Its outer wall is composed of silk‑like fibers interlaced with fecal debris, creating a brownish‑gray coating that blends with the surrounding material. Inside, the pupa is a compact, immobile stage with a hardened exoskeleton that darkens to a reddish‑brown hue as maturation proceeds. The pupa’s head and thorax are concealed, leaving only the terminal abdominal segment exposed, from which the emerging adult will later break through.
Key visual traits:
- Larva
- Length: 2–5 mm
- Color: milky white, translucent
- Body: three regions, three pairs of legs, numerous setae
- No eyes, antennae, or wings
- Pupa
These characteristics enable reliable identification of flea immature stages during inspection of infested habitats.