What do house bedbugs look like? - briefly
House bedbugs are small, flat, reddish‑brown insects about 4–5 mm long with oval, wingless bodies and visible antennae. After a blood meal they expand, becoming larger, paler, and more rounded in shape.
What do house bedbugs look like? - in detail
House-dwelling bedbugs are small, oval insects measuring 4–5 mm when unfed and expanding to about 6–7 mm after a blood meal. Their bodies are flat and dorsoventrally compressed, allowing them to hide in tight crevices. The exoskeleton is a matte, reddish‑brown color; newly emerged individuals appear pale, almost translucent, and darken with each molt.
Key visual characteristics:
- Shape: Elongated oval, resembling a tiny apple seed.
- Color: Reddish‑brown after feeding; lighter, tan‑gray before feeding.
- Surface texture: Non‑shiny, with fine hairs covering the thorax and abdomen.
- Head: Small, concealed beneath the pronotum, with short, needle‑like mouthparts adapted for piercing skin.
- Antennae: Four segmented, slender, and lie flat against the body.
- Legs: Six, each ending in tiny claws that grip fabric fibers.
- Abdomen: Six visible segments; after a meal the abdomen swells and takes on a more pronounced, rounded silhouette.
- Eyes: Simple ocelli, not prominent, usually hidden under the head capsule.
Eggs are about 0.5 mm in length, white to off‑white, and stick together in clusters of 10–50. Nymphs resemble adults but are uniformly lighter and lack the deep reddish hue that appears after feeding. Each nymphal stage requires a blood meal before molting to the next instar, resulting in gradual darkening and size increase.
The combination of flat, oval shape, matte reddish‑brown coloration, visible antennae, and six‑legged arrangement distinguishes domestic bedbugs from other household insects such as carpet beetles, fleas, or cockroaches. Their ability to expand dramatically after feeding provides a reliable indicator: a swollen, darkened abdomen signals a recent blood meal.