How do all types of bedbugs look? - briefly
All bedbug species are small, wing‑less, oval insects about 4–5 mm long, reddish‑brown when unfed and expanding to a swollen, lighter‑colored abdomen after a blood meal. The common bedbug (Cimex lectularius) and the tropical bedbug (Cimex hemipterus) share this morphology, differing only in minor size and geographic distribution.
How do all types of bedbugs look? - in detail
Bedbugs belong to the family Cimicidae and exhibit a consistent oval, dorsoventrally flattened body that enables concealment within fabric seams. Size, coloration, and subtle morphological traits differentiate the principal species that infest humans and other vertebrate hosts.
-
Cimex lectularius (common human bedbug) – Adult length ranges from 4.5 mm to 5.3 mm; width approximates 2.5 mm. Color varies from reddish‑brown after a blood meal to lighter tan when unfed. The exoskeleton lacks visible wings; forewings are reduced to hardened hemelytra covering the abdomen. Antennae consist of five slender segments, each bearing fine sensory hairs. Legs are long relative to body width, terminating in two tarsal claws that facilitate gripping textiles.
-
Cimex hemipterus (tropical human bedbug) – Dimensions similar to the common species, typically 4.5 mm to 5.0 mm in length. Body coloration leans toward a darker mahogany hue, persisting even after engorgement. The dorsal surface exhibits a slightly more pronounced dorsal ridge, aiding identification under magnification. Antennal and leg morphology mirror the common species, though the tibiae display a faintly lighter band near the joints.
-
Cimex pilosellus (bat bug) – Adult size extends to 6 mm–7 mm, larger than human‑associated species. Coloration is a deep brown to black, often with a glossy sheen. The abdomen is more robust, with a pronounced posterior taper. Legs are heavily setose, providing enhanced traction on the coarse fur of bat hosts. Wing pads remain reduced; no functional wings are present.
-
Oeciacus vicarius (swallow bug) – Length measures 5 mm–6 mm; body color ranges from reddish‑brown to dark brown. The head is proportionally broader, and the pronotum exhibits a distinct lateral ridge. Antennae are shorter than in human bedbugs, with the third segment noticeably thickened. Legs are equipped with robust spines, reflecting adaptation to nesting material of swallows.
-
Paracimex sp. (cave‑dwelling bedbug) – Adults reach up to 5.5 mm. Dorsal coloration is pale brown, often with a faint mottled pattern. The exoskeleton bears minute punctate markings across the thorax. Antennae are elongated, with the terminal segment ending in a small sensory cone. Leg morphology includes elongated femora, facilitating rapid movement across rocky substrates.
All species share the characteristic lack of functional wings, a piercing‑sucking rostrum adapted for hematophagy, and a segmented abdomen divided into visible dorsal plates. Variations in size, coloration, and setation reflect adaptation to specific hosts and environments, providing reliable criteria for taxonomic identification.