What do domestic bedbugs look like and what are their sizes? - briefly
Domestic bedbugs are flat, oval-shaped, reddish‑brown insects with a pointed head and visible antennae. Adults measure roughly 4–5 mm in length, while immature stages range from 1 mm to 3 mm.
What do domestic bedbugs look like and what are their sizes? - in detail
Domestic bedbugs are small, wing‑less insects belonging to the family Cimicidae. Adults possess a flat, oval body that is broadest at the abdomen and tapers toward the head. The dorsal surface is covered by a hardened shield (pronotum) that is darker than the lighter, reddish‑brown abdomen. Four short antennae emerge from the head, and each side bears three pairs of legs ending in tiny claws. The mouthparts form a beak‑like proboscis used to pierce skin and draw blood.
Size varies with developmental stage and feeding status:
- Egg: ~0.5 mm long, oval, white, attached to surfaces with a sticky secretion.
- First‑instar nymph: 1.2–1.5 mm, pale yellow, translucent.
- Second‑instar nymph: 1.5–1.8 mm, slightly darker.
- Third‑instar nymph: 1.8–2.2 mm, more reddish.
- Fourth‑instar nymph: 2.2–2.5 mm, approaching adult coloration.
- Unfed adult: 4.5–5.5 mm in length, 1.5–2.5 mm in width, reddish‑brown.
- Engorged adult: expands to 7–10 mm long and 3–4 mm wide, abdomen becomes balloon‑like and lighter in color.
Key visual markers include the visible “c‑shaped” or “U‑shaped” feeding scars on human skin, the presence of tiny dark spots (excrement) on bedding, and the characteristic odor of a sweet, musty smell when populations are large. The insect’s body flattens further after feeding, allowing it to hide in cracks, seams, and mattress tufts. These morphological and dimensional details enable accurate identification and effective control measures.