What do flea larvae look like?

What do flea larvae look like? - briefly

Flea larvae are small, legless, worm‑like insects about 2–5 mm long, with a translucent, cream‑colored body and a dark head capsule. They have short bristles and a curved, C‑shaped posture within the debris where they develop.

What do flea larvae look like? - in detail

Flea larvae are elongated, worm‑like organisms measuring 2–5 mm when fully grown. Their bodies are soft, translucent to creamy‑white, and lack a hardened exoskeleton. The exterior consists of 13 visible abdominal segments, each separated by shallow grooves that give the larva a slightly banded appearance.

The anterior region houses a small, rounded head without eyes. Mouthparts are concealed beneath a short labrum and consist of chewing mandibles adapted for consuming organic debris, fungi, and detritus. Antennae are reduced to a pair of sensory hairs (cerci) that detect vibrations and chemical cues in the environment.

Respiration occurs through a pair of spiracles located laterally on the eighth abdominal segment. These openings are surrounded by thin, membranous cuticle and allow passive gas exchange; larvae do not possess active breathing structures.

Locomotion is achieved by rhythmic contractions of the body wall, producing a sinusoidal crawling motion. The ventral side bears a thin layer of mucus that facilitates movement through the fine sand, hair, or fabric where larvae develop.

Key visual characteristics:

  • Length: 2–5 mm, increasing with each instar.
  • Color: translucent to off‑white; may appear slightly yellowish when fed.
  • Body: soft, segmented, lacking sclerotized plates.
  • Head: small, eyeless, with concealed chewing mandibles.
  • Sensory structures: short cerci, tactile hairs.
  • Spiracles: lateral, on abdominal segment 8.
  • Movement: undulating crawling aided by mucus secretion.

These traits distinguish flea larvae from other small insects and aid in their identification during pest‑inspection procedures.