What is the bug that smells like a bed bug? - briefly
The insect in question is the common bed bug (Cimex lectularius), which emits a distinctive sweet‑musty odor often likened to coriander or mold. This scent is a defensive secretion produced when the bug is disturbed.
What is the bug that smells like a bed bug? - in detail
The insect that releases an odor most often compared to the scent of a bed‑bug is the stink bug, particularly members of the Pentatomidae family such as the brown marmorated stink bug (Halyomorpha halys).
When disturbed, stink bugs exude a volatile mixture of aldehydes, alkanes and short‑chain fatty acids. The blend produces a sweet, musty, coriander‑like smell that many people mistake for the characteristic odor of a bed‑bug when it is crushed or frightened.
Key points about the stink bug’s odor:
- Chemical basis – Primary compounds include trans‑2‑hexenal, trans‑2‑octenal and hexanal, which together generate the familiar sweet‑musty profile.
- Defensive purpose – The scent is released from glands on the abdomen to deter predators; it is not a by‑product of feeding as with bed‑bugs.
- Comparison to bed‑bug odor – Bed‑bugs emit a mildewy, slightly sweet odor derived from their own cuticular hydrocarbons. Both insects produce a smell that can be described as “coriander‑like,” leading to confusion in field identification.
Distinguishing features:
- Body shape – Stink bugs have a shield‑shaped, dorsally flattened body, whereas bed‑bugs are oval and flatter on the underside.
- Size – Stink bugs range from 10–20 mm in length; adult bed‑bugs are typically 4–5 mm.
- Behavior – Stink bugs are primarily plant feeders and are often found on leaves or inside homes during autumn; bed‑bugs are hematophagous and hide in crevices near sleeping areas.
Understanding the chemical and morphological differences helps avoid misidentification when the characteristic odor is the primary clue.