How can you identify a female bedbug? - briefly
Female bedbugs are larger (5–7 mm) and have a broader, rounded abdomen that swells after a blood meal, whereas males are smaller and slimmer. They also display a visible ovipositor near the rear, a structure absent in males.
How can you identify a female bedbug? - in detail
Female bedbugs can be distinguished from males by examining several anatomical features observable under a hand lens or microscope.
The abdomen of a mature female is markedly broader and more rounded, especially after a blood meal, because it expands to accommodate developing eggs. In contrast, a male’s abdomen remains relatively slender and tapered.
The ventral surface of a female bears a smooth, unobstructed plate, while males possess a distinct, hardened structure called the spermalege—an inverted “V” or groove used during copulation. The absence of this feature indicates a female.
A female’s terminal abdominal segment terminates in a short, blunt ovipositor tip, whereas a male ends with a pointed genital capsule. This difference is visible when the insect is positioned laterally.
Egg development produces a visible “egg belt” or line of eggs within the abdomen of a gravid female; this line is absent in males.
Additional cues include:
- Size: females are generally 5–7 mm long, slightly larger than males (4.5–6 mm).
- Coloration: both sexes share the same reddish‑brown hue after feeding, but the expanded abdomen of a fed female may appear darker due to increased blood volume.
To confirm sex, gently straighten the insect and observe the ventral side. The combination of a broad abdomen, lack of a spermalege, and presence of an ovipositor provides reliable identification of a female bedbug.