Bed Bug (Cast Skin/Exuvia)
Scientific Name: Cimex lectularius
Order & Family: Order: Hemiptera, Family: Cimicidae
Size: Commonly 4-5 mm (adults), but nymphs can be as small as 1.5 mm. Cast skins vary in size depending on the nymphal stage.
Natural Habitat
Found indoors, primarily in bedrooms and sleeping areas. They hide in cracks and crevices of mattresses, box springs, bed frames, headboards, and surrounding furniture.
Diet & Feeding
Hematophagous (blood-feeders). They feed exclusively on the blood of warm-blooded animals, preferring humans.
Behavior Patterns
Nocturnal feeders that hide during the day. They go through 5 nymphal stages, shedding their skin (molting) at each stage to grow. This image depicts one of these shed skins (exuviae), which are often found in clusters near harboring areas.
Risks & Benefits
Risks: Their bites cause itching, allergic reactions, and secondary skin infections from scratching. They cause significant psychological distress and anxiety. They are not known to transmit disease to humans. Benefits: None known.
Identified on: 2/18/2026