How to Identify Bed Bugs

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bed bug identification

Bed bugs (Cimex lectularius) are six-legged insects that feed on blood, usually at night. These pests are notoriously difficult to get rid of, and they easily spread to new locations by crawling into neighboring apartments or hitching rides in bags, luggage, used furniture, clothing, and other personal items.

Treatment for bed bugs starts with a thorough inspection of infested areas (ideally with a certified bed bug detection canine) followed by professional pesticide application or ambient heat treatment.

  • Bites
  • Musty odors
  • Bloodstains on sheets
  • Fecal marks
  • Shell casings
  • Bed bug eggs

Bed bug bites often go unnoticed because they feed at night while people are asleep. Their saliva also contains an anesthetic to prevent pain from waking their host up.

Areas bitten by bed bugs may appear as small clusters of itchy red bumps on hands, legs, and other areas of the body.

Bites may also cause rashes, allergic reactions, psychological distress, or nothing at all (approximately 30-60% of people have no visible reaction to bed bug bites).

If you’re need help with bed bugs in New York or the Tri-State Area, contact MMPC for NESDCA-certified K9 inspections and eco-friendly bed bug treatments.


Adult bed bugs feed on blood approximately every 3–7 days. They often come out to bite at night, most commonly between midnight and 5:00 am.

Bed bugs locate their hosts by detecting carbon dioxide (from breathing), body heat, and body odor.

During the day, bed bugs like to hide in dark, narrow spaces like seams and crevices in mattresses, bed frames, and walls.

Size: 1/6″ – 1/4″ long (4 – 7 mm); about the size of a flax seed or small apple seed

Color: Reddish-brown or mahogany

Shape: Wingless, flat, oval-shaped body with a large abdomen, short antennae and 6 legs; elongates after a blood meal


Bed bug nymphs have 5 instar stages, becoming progressively larger and darker in color. Between each stage, the growing nymph molts and leaves behind a hollow shell casing.

These baby bed bugs are sometimes mistaken for cockroach nymphs, booklice, and other insects due to their small size and light-colored, translucent appearance.

Like adult bed bugs, nymphs also feed on blood at night and hide during the day.

Size: As small as 1/16″ (1.5 mm)

Color: Yellowish white or light brown

Shape: Similar to adults but smaller and more translucent

  • 6 thin legs
  • Short antennae with 4 segments, bowing outwards
  • Small head with beady eyes
  • Squarish, protruding mouthparts (proboscis)
  • Wide dorsal plate (pronotum)
  • Flat, oval abdomen with 8 sclerites
  • If recently fed, you can see a red or dark-colored blob of digested blood inside its translucent body