What do adult bedbugs look like? - briefly
Adult bedbugs are wingless, oval insects about 4–5 mm long, with a flat, reddish‑brown body that becomes paler after feeding. They possess six legs, a pointed head, and visible dark spots on the dorsal surface.
What do adult bedbugs look like? - in detail
Adult bedbugs measure approximately 4.5–5.5 mm in length and 1.5–3 mm in width when unfed. Their bodies are oval, flat dorsally, and become swollen after a blood meal, reaching up to 7 mm. The exoskeleton is a matte, reddish‑brown hue that darkens to a deeper mahogany after feeding and fades to a lighter tan during the next molt.
Key morphological characteristics include:
- Head: Small, concealed beneath the pronotum; equipped with a pair of elongated, bean‑shaped antennae bearing 5 segments.
- Eyes: Two compound eyes positioned laterally on the head, each composed of numerous ommatidia.
- Mouthparts: Piercing‑sucking proboscis (rostrum) extending forward, adapted for penetrating skin and extracting blood.
- Thorax: Pronotum broadens posteriorly, covering the head and providing a smooth, rounded appearance.
- Legs: Six legs, each ending in a curved claw; legs are slender, allowing rapid crawling across fabrics and mattress seams.
- Abdomen: Segmented with a series of dorsal plates (tergites) that display faint parallel lines; ventral side bears a smooth, glossy surface.
Coloration shifts with nutritional status. Unfed individuals appear light brown, while engorged specimens display a pronounced reddish‑black abdomen, sometimes with a visible white or yellowish spot at the posterior end where the anus opens. After digestion, the abdomen returns to a lighter shade, and the insect resumes its flattened profile.
The lack of wings distinguishes adult bedbugs from many other hematophagous insects. Their body is covered with fine, hair‑like setae that provide sensory feedback, aiding navigation in dark, confined environments such as mattress seams, upholstery folds, and wall crevices. These features collectively enable the insect to locate hosts, feed efficiently, and hide effectively during daylight hours.