What do different species of bedbugs look like? - briefly
Common bedbug (Cimex lectularius) is reddish‑brown, flat, oval, about 4–5 mm long; the tropical counterpart (Cimex hemipterus) is lighter‑colored, slightly larger, and more elongated. African and Australian relatives such as Afrocimex and Paracimex retain the oval shape but often exhibit darker pigmentation or subtle thoracic extensions.
What do different species of bedbugs look like? - in detail
Bedbug species exhibit subtle but diagnostic variations in size, coloration, body proportions, and surface texture. The most frequently encountered members are described below.
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Cimex lectularius (common bedbug) – Adult length 4.5–5.5 mm, oval dorsoventrally flattened body, reddish‑brown after feeding and pale tan when unfed. Head concealed under pronotum, antennae four‑segmented, each segment bearing a short setae. Abdomen bears a faint pale stripe along the midline. Legs are slender, with tibiae bearing fine spines.
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Cimex hemipterus (tropical bedbug) – Similar overall shape to the common species, but typically 5.0–6.0 mm long. Coloration ranges from deep mahogany to orange‑brown. Pronotum exhibits a more pronounced lateral margin, and the dorsal surface shows a subtle speckled pattern visible under magnification. Antennae are proportionally longer, reaching the anterior edge of the thorax.
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Leptocimex boueti (African bedbug) – Length 3.5–4.0 mm, markedly smaller than the two previous species. Body surface appears matte rather than glossy, with a uniform light brown hue. Pronotum is narrower, and the wings (if present) are reduced to vestigial pads. Legs are relatively robust, ending in broader tarsi.
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Haematosiphon inodorus (bat bug) – Adults reach 6.0–7.0 mm, the largest among human‑associated cimicids. Color ranges from dark brown to almost black; the abdomen may display faint pale bands. Antennae are elongated, extending beyond the pronotum. The dorsal surface is densely covered with fine hairs, giving a slightly fuzzy appearance. Hind legs possess enlarged femora adapted for clinging to fur.
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Oeciacus vicarius (bird bug) – Size 5.0–5.8 mm, body slenderer than Cimex species. Dorsal coloration varies from light gray to brown, often with a distinct pale longitudinal line. Pronotum shows a sharp, raised ridge. Legs are slender with reduced spination, reflecting adaptation to feathered hosts.
Morphological distinctions extend to the genital capsule of males, which differs in the shape of the parameres and median process, providing reliable species‑level identification under microscopic examination. Egg morphology also varies: Cimex eggs are oval, 0.9 mm long, with a smooth chorion, whereas Haematosiphon eggs possess a slightly ridged surface and are marginally larger.
Collectively, these traits enable entomologists to separate bedbug taxa without reliance on molecular methods, supporting accurate surveillance and control efforts.