All this type of beetle are of the Family
Dermestidae. The members of this family live primarily on
the dried remains of plants and animals. Many species live, for example,
on cartilage and dried meat, and some can utilise hair and feathers. This
way of life will of course bring them into contact with human interests,
for they frequently attack dried foodstuffs.
adult larder beetle is dark brown and approximately 1/3 inch in length.
The basal halves of the wing covers are densely covered with coarse, pale
yellow hairs. Six dark spots are usually in the yellow band. The undersurface
of the body and legs are covered with fine yellow hairs.
the life cycle of this insect is regulated by the seasons; indoors it
may breed continuously throughout the year. Eggs are laid in batches of
6-8, with the total per female being about 200. The larvae are dark coloured
and covered with dark brown hairs. It is characterised by two curved spines
on the last body segment. Like the adult, the larva is densely covered
with hairs. The larvae pass through five or six moults ( five
times if male, and six if female), during
the 35 to 80 days of their lives. The larvae have a strong tendency to
remain in dark places. Just before the larvae pupate they begin to migrate,
and are often encountered by homeowners at this time. These older larvae
often bore into materials such as wood, cork, or insulation looking for
a place to pupate. The pupal period lasts about 15 days. The adults mate
soon after emerging and eggs are laid near a food source. If conditions
are ideal, a generation may be completed in 40-50 days.
damage occurs from larval feeding and the boring of the larvae before
pupation. Larder beetles will attack stored ham, bacon, other meats, cheeses,
tobacco, dried fish, dried museum specimens, and pet foods, for example.
All of these conditions are available in, meat processing plants, renderers,
butchers, fishmongers, delicatessen counters in supermarkets and, of course,
beneath and behind cookers and refrigerators in the kitchen of a domestic
dwelling. The larvae will bore into any commodity containing meat products;
they have also been known to bore into structural timbers. Tests have
shown that they can bore into lead with ease and tin with some difficulty.
The boring is for the purpose of providing a protected place for pupation,
not for feeding. The picture below shows damage to timber caused by larder
beetle larvae boring in to pupate.
courtesy of Jim Kalisch, University of Nebraska.
inspection, and elimination of infested food sources are the first steps
in controlling this pest. Valuable materials which are infested can
be heat sterilised (140°F for 1/2 hour) or frozen (0° for 3-4
days). Place food materials that might attract beetles into tight jars
or cans to discourage re-infestation. Once the cleaning has been undertaken,
perhaps a light spray with a residual insecticide to wall/floor junctions
and potential harbourage sites, remembering of course not to spray near
food. If the infestation has been particularly bad and the business
caters directly to the public, then it might be a good idea to have
a contract with a pest control company so that the premises are treated
and inspected on a regular basis.
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