What do the black spots of bedbugs look like? - briefly
They are tiny, dark brown‑black punctate marks roughly 1–2 mm across, resembling specks of pepper. The spots are fecal stains or shed exoskeleton fragments commonly seen on sheets, mattress seams, and nearby walls.
What do the black spots of bedbugs look like? - in detail
The dark markings on Cimex lectularius are small, matte‑black puncta located on the dorsal surface of the adult insect. Each spot measures roughly 0.1–0.2 mm in diameter, appearing as a single point or a cluster of two to three adjacent dots. The coloration is uniform, lacking any iridescence or sheen that might be seen on other body parts. Spots are positioned near the center of the thorax, often aligned symmetrically on either side of the midline, and may extend toward the posterior abdomen in some specimens.
Key visual characteristics:
- Size: 0.1–0.2 mm, comparable to the tip of a fine sewing needle.
- Shape: Round to slightly oval, with crisp edges.
- Color: Deep black, non‑reflective, contrasting sharply against the reddish‑brown exoskeleton.
- Distribution: Typically one spot per hemithorax; occasional additional spots on the abdomen in mature individuals.
- Texture: Smooth, not raised; the spots are part of the cuticle rather than pigmentation on underlying tissues.
Under magnification (10–40×), the spots remain consistent in intensity, showing no variation in hue across individuals. In nymphal stages, the markings are less pronounced or absent, becoming fully developed only after the final molt. The presence and pattern of these black puncta are reliable diagnostic features for confirming the species and distinguishing adults from other hematophagous insects.