One of the most recognizable household pests is the larder beetle. Both the adults and larvae have characteristic features that readily distinguish them from other insects.
This insect is very common and widespread and is a frequent pest in homes. The insect's name comes from it's presence in dried, cured meats stored at room temperature prior to refrigeration. Today, larder beetles may be a pest in stored foods but are more likely to be only an annoyance because of their presence in the house.
The larder beetle adult is slightly longer than 1/4th inch. It is roundly oval and dark brown to black with a characteristic light colored band running across the body. This light band contains 6 more or less prominent dark spots. Larder beetle larvae are up to 1/2 inch long. They are tapered in shape and covered with sparse, stiff hair. There are 2 upward curved spines on the posterior end.
Both the larvae and adults feed on items such as fur, hair, hides, feathers, and occasionally stored products such as dried fish, pet food and cheese. They will also feed on dead animal matter, such as dead boxelder bugs, attic flies or mice that may be in the innerwall spaces of the house. This last source is the most likely in an infested house.
When a larder beetle infestation occurs in a cupboard or storage closet, all food items should be removed and the infested products discarded. The shelves should be thoroughly vacuum cleaned and the materials inspected before returning them to the cupboards. If the infestation is more general in nature and specific source(s) of the insects cannot be located, a general control process may be helpful. Thoroughly vacuum clean cracks and crevices in the areas where larder beetles are found. A residual insecticide treatment can be applied to these areas following cleaning. Readily available insecticides for homeowner use include the "ant and roach killers" and the "home pest control" products found in grocery and hardware stores and garden centers.
This article originally appeared in the April 6, 1994 issue, p. 44.