Bed bugs

(Cimex lectularis; Cimex hemipterus)

Cimex lectularis is found in temperate countries while Cimex hemipterus (=C. rotundatus) occurs in tropical countries. Bed bugs are not known to transmit any disease, although they are suspected to be vectors of kala-azar and relapsing fever.

Body is reddish-brown, dorsoventrally flattened. Proboscis is segmented and is used for piercing the host skin and sucking blood. Maxillary palps are absent. Antenna is 4-segmented. Pronotum is shield like having lobes on either side of the head. Tarsis is 3-segmented. Wings are absent but rudimentary pads are present.

There are stink glands all over the body which emit a characteristic foul odor. In male posterior end of abdomen is produced into a lobe and is hairy with a spine-like aedeagus. In female abdomen is broadly rounded posteriorly having small hairs. Fourth abdominal segment in female possesses an organ of Berlese on the ventral side to the right side of the middle. This is a pouch-like structure in which sperms are stored after copulation. Sperms from here bore through the walls and tissues and fertilize eggs in the ovaries.

 Eggs are whitish, 1.0 mm long, flask-shaped, having reticulated surface and an operculum on the anterior side. They are laid among the bedding, in cracks and crevices of the walls and floor or any other hidden situations. Many females lay their eggs in groups at one place. Fecundity is 75-200 eggs/female. Incubation period is generally 6-10 days but in hot season may be reduced.

Nymphs similar to the adults and suck blood. First instar nymphs are semitransparent and later instars are straw yellow. There are 5 nymphal instars which take about 30 days to become adults. Adults are nocturnal and both sexes suck blood. They can resist starvation up to six months. The starving individuals look light coloured and extremely thin. They can regain dark brown colour and original form after sucking blood.

Control of bedbugs

Cement plastering of cracks on the floor and walls and periodic white washing of the house and maintenance of cleanliness helps to eradicate bugs.

Exposing bedding and infested articles in the sun periodically and boiling clothes in water kills them.

Spray of DDT 5%, BHC 6% or malathion and endosulfan dust 5% in houses and cots and beds kills them. Dusting helps to eradicate them more effectively.

 Predators of bed bugs

Small red house ant, Monomorium pharaonis.

Rduvius personatus, the assassin bug.

The pseudoscorpion, Chelifer cancroids.