蟑螂的种类与危害 Categories of black beetles and their dangers
Cockroach is also called dictyoptera and belongs to blattaria
of insecta. Up to now, 5000 species have been discovered, including
house cockroaches and house cockroaches. The harmful species are
mainly periplaneta Americana, periplaneta Australasiae, speckle
periplaneta and blattella Germanica. Among which, periplaneta Americana
is a dominant species. Cockroach does great harm to people's health.
It carries more than 40 kinds of virus and bacteria, mainly including
bacillus pestis, comma bacillus, salmonella, bacillus pyocyaneus,
staphylococcus aureus and pneumococcus, etc. Besides, cockroach
also pollutes commodities, industrial products and food, etc.
蟑螂的危害可概括为如下2类： There are two kinds of harms brought by cockroach:
Disturbance: It disturbs people's sleep and rest. In addition,
it attacks infants and a bite may lead to allergy or itch
It destroys articles and food, or causes computer breakdown or
It causes skin allergy and abnormal reaction of respiratory system
.Its excrement may also cause and/or worsen asthma of the patients
with hypersensitive constitution.
Cockroach carries a variety of pathogenic microorganisms such
as bacteria, virus, protozoon, parasitic ovum and fungi, etc. In
normal conditions, pathogens will not reproduce themselves in the
body of cockroach, thus it is mainly a mechanical spreading media.
But due to its extensive harm, omnivorous habit and skilful hiding
ability, as well as its frequent touch with medical equipment, food,
and food processing equipment, we should not overlook the danger
of possible epidemic diseases caused by it!
Periplaneta Americana：The largest in-house cockroach with
body length of 25-40mm. The male ones and female ones are
about the same size, but the latter look fatter. Body in brownish
red, with yellow brim. There is a brown disk-shaped spot on
the front back and the central line of the spot extends to
the rear, with a T-shaped yellow stripe at the front end of
the central line. The imago has strong wings and the female's
wings go beyond the end of the abdomen.
Periplaneta Australasiae：Body in brown. Smaller than periplaneta
Americana. It has a similar front back to that of Periplaneta
Australasiae, with the same yellow-colored brim, but the central
line of the disk-shaped spot is not extended. There is not
a T-shaped yellow stripe at the front end of the middle line.
Yellows stripes can be seen on the upper corner brim of the
Neostylopyga rhombifolia：Smaller than periplaneta Americana
and body in brown; there are anchor-shaped spots on the center
of front back. The imago has fully-developed strong wings
extending to the end of the abdomen. The major difference
between speckle periplaneta and Periplaneta Americana lies
in their front back and the shape of circus. The circus of
the former is short and blunt-ended while that of the latter
is the opposite; the former's epiproct, is short and small,
and the latter long and big, with a deep notch in the center
Blattella Germanica：The smallest in-house cockroach, with
a length of 10-15mm. Body in brown. There are two parallel
brown stripes on the front back. The imago has strong wings
How to distinguish male and female cockroaches: Male cockroach
is relatively thinner but longer, with a ventral spine and fully
developed wings reaching the rear; Female has shorter wings and
no ventral spine.