其他害虫种类与危害 Harms by other pests
Biological behavior and harms of ants：
Ant belongs to formicidae, hymenotera, insecta. It is a social
insect with a high degree of division of labor, as well as a nidificant
and gregarious polymorphic insect. It usually consists of gyne,
ergate and dinergate (derived from ergate). The mating ants have
wings while ergate and dinergate do not. The life cycle of an ant,
from ovum to larva to pupa and then to adult, takes 6 to 8, with
a life span of 15 years. Ergates are commonly seen in the house.
Commonly seen species of ants include small yellow ant, Pheidole
rhombinoda, Tetramorium caespitum and Iridomyrmex.
Apart from disturbance and bite, the major harm of ants is its
pollution to food which may cause infection. An ant carries various
kinds of pathogens, such as diamond-shaped bacillus, salmonella,
staphylococcus and streptococcus, etc.
Cterolepisma villosa Fabricius
Cterolepisma villosa Fabricius is a pest belongs to lepismidae,
thysanura and insecta. The male adult is apteral, with a length
of 9-13mm. There are black scales on the back and white scales on
the abdomen. Its chest is wider than the abdomen, and the abdomen
gradually narrows from the base to the end. Its nymphae is identical
to adult in shape, but smaller in size, and infant nymphae has no
Cterolepisma villosa Fabricius is an insect of incomplete metamorphosis
which reproduces several generations a year. Both its nymphae and
adult are noctural, favor darkness and thus hind in all kinds of
crevices. It is mainly found in places where there is starch. It
damages grain and food, as well as gnaws books, periodicals, papers
and documents, etc.
Living habits and harms of flea
Flea belongs to siphonaptera, insecta and arthropoda. It is an
insect of complete metamorphosis, this its growth process includes
four stages, namely ovum, nymphae, pupa and adult. It not only bites
and sucks blood, but also transmit plague, mice-borne typhus. It
mainly parasitizes on surface of mammals and birds. It has distinct
features in shape and the process of development by metamorphosis
so as to parasitizes on the host and suck blood. The adult is small
is size, usually 1-3mm long; Both male and female ones suck blood;
dark or yellowish brown, with no wings; It has three pairs of strong
legs suitable for hopping (especially the hind legs); There is powerful
claws on its fifth tarsus.
A bite by Pulex irritans, Ctenocephalides felis and Ctenocephalides
canis will not only cause excitation and pain, but also allergic
reaction of certain degree. A flea sucks blood several times a day,
so it severely influences people's life. Some fleas, Tunda penetrans
for example, may parasitize in people's subcutaneous tissue and
thus does more severe harm. When livestock or pets are bit by a
large number of fleas, its growth will be hindered. More importantly,
it can cause anemia.
Biological behavior and harms of pediculus
Anoplura, other named louse, is an insect of gradual metamorphosis
that belongs to anoplura of insecta. Its life cycle consists of
three stages, namely ovum, nymph and adult. It is an obligatory
parasite on the surface of birds and mammals. It can not live without
a host in all three stages of life. Louse disturbs people's life
and transmits various commutable diseases such as endemic typhus,
trench fever and relapsing fever.
Lice like to cluster on the collar of underwear, slot and waist
of trousers. The nymph of louse and female adults suck blood, at
least once a day and several times a day respectively. A louse usually
sucks blood while defecating.
When a louse sucks blood, it injects its saliva which may lead
to obvious skin reactions. Secondary infection is likely to occur
if the spot is scratched, and will further cause pustule. The bloodsucking
louse also transmits various commutable diseases such as endemic
typhus, trench fever and relapsing fever. The outbreak of these
diseases is usually related to war and natural disasters, since
the sanitary conditions deteriorate and people are more likely to
get together on such occasions, thus favorable to spread of lice.