Chapter 10 Flashcards
- Bugs
- Beetles
- Bugs (Hemiptera)
- Beetles (Coleoptera)
what does the name Hemiptera mean?
The name Hemiptera means ‘halfwing’ which refers
to the fact that part of the first pair of wings is
toughened and hard, while the rest of the first pair
and the second pair are membranous
What are some facts about bed bug, Cimex lectularius?
- It lives in bedding and is mainly active at night, feeding
on human blood, generally without being noticed
Bed bugs mate by traumatic insemination;
Explain how the male bed bugs inseminate the females bed bugs.
Bed bugs mate by traumatic insemination; the male
pierces the female’s abdomen and injects his sperm
into a secondary genital structure (spermalege)
* The sperm travel in the female’s blood (haemolymph)
to sperm storage structures (seminal conceptacles);
they are released from there to fertilise her eggs inside
her ovaries
(see slide 20)
The family Cimicidae includes bed bugs, of which
two common species feed on human. What are they?
Cimex lectularius is widely distributed in tropical
and nontropical countries while C. hemipterus,
commonly called the tropical bed bug, is essentially
a species of the Old and New World tropics
What is the species of the family Cimicidae?
A third species, Leptocimex boueti, is found mainly
in West Africa but has also been recorded in South
America. This species bites bats and also people,
but is much less important as a pest than the Cimex
species
When did the Infestations of bed bugs start to increase?
- Infestations of bed bugs have increased since the
1990s in many countries, possibly due to increased
global travel. For instance, after the 2000 Olympic
Games nearly every hotel in Sydney was infested
with bed bugs
What are other ways bed bugs?
- Bed bugs are usually spread to new houses by
being introduced with furniture and bedding, or
more rarely with clothing and hand baggage.
Buying second hand furniture can result in the
introduction of bed bugs into houses
State morphologies of bed bugs.
- Adult bed bugs are oval, wingless insects which are
flattened dorsoventrally - The head is short and broad and has a pair of
prominent compound eyes - The prothorax is much larger than the meso- and
metathorax - Bed bugs lack wings so they do not disperse far
How many wings do bed bugs have?
Two rudimentary and non-functional more or less oval
wing pads, termed hemelytra, overlie the meso- and
metathorax
Difference between the morphology of female bed bugs and male bed bugs
In adult males the tip of the abdomen is slightly more
pointed than in females, while closer examination
shows a small well-developed curved penis
* In females there is a small incision ventrally on the left
side of the apparent fourth abdominal segment. This
opens into a special pouch (=sinus) called the
mesospermalege, organ of Berlese or organ of Ribaga,
which collects and stores sperm
* Because both male and female bugs bite it is not
medically very important to distinguish the sexes
What happens to bed bugs during the day and night?
During the day adults and nymphs are inactive and hide in dark
and dry places, such as cracks and crevices in furniture, walls,
ceilings or floor boards, underneath seams of wallpaper and
between mattresses and beds. At night adults and nymphs
emerge to feed on sleeping people, after which they return to
their resting sites to digest their blood-meals. Bed bugs are
gregarious and are frequently found in large numbers. They can
move quite rapidly when disturbed
Bed Bugs (Hemiptera) – Life Cycle
- Females lay about 2–4 eggs a day in cracks and
crevices of buildings and furniture, but egg-laying
ceases at 13° C or lower. Females live several weeks
to many months, and occasionally a year or more,
and during this time they may lay 150–540 eggs - Eggs usually hatch after about 8–11 days
- Newly hatched bed bugs (nymphs) are very pale
yellow and resemble adults, but are much smaller - The life cycle is hemimetabolous and there are five
nymphal instars each lasting 3–10 days.
The nymphal period lasts 2–7 weeks - The life cycle, from egg to adult, can be just 3–4
weeks if temperatures are high and food plentiful,
but is more usually 6–10 weeks - In the laboratory adults can live for four years, and
survive more than a year without blood-feeding
Bed Bugs (Hemiptera) – Life Cycle
Bed Bugs (Hemiptera) – Medical Importance
- Although hepatitis B virus and 27 other pathogens
have been recorded in bed bugs there is no
evidence that they can transmit any infections to
people. They are therefore not considered as
vectors
Can bed bugs cause iron deficiency?
Some people show little or no reaction to their
bites, but others may suffer severe reactions and
have sleepless nights. Repeated feedings of large
numbers of bed bugs can cause iron deficiency in
infants and some elderly people
