Aug 2, 2012 – Food or Wood – It Really Matters

QUESTION:

I have a sample of what looks like drugstore beetles a customer is seeing in the kitchen of their house. They had them identified by another source that said they were Anobiids. They indeed did have Anobiid in the substructure that we have treated for. My concern is these sample beetles are not Anobiid and they have a drugstore beetle problem also. As the two beetles are very similar, what can I look for to distinguish one from the other?

ANSWER:

Ah yes, the importance of that accurate ID. Is it eating the woodor eating their food, and obviously knowing which one it is matters greatlywhen it comes to control. Drugstore and Cigarette beetles are common stored food pests and they are in the family Anobiidae. Also in this beetle family are Deathwatch and Furniture beetles, and there may be some superficial resemblance. However, drugstore beetles are pretty darned distinct. They are dark brown, slightly hairy and with an overall dull (not shiny) caste, and their antennae consist of several short segments at the base followed by 3 much larger, much longer segments that compose the outer 2/3 of the antenna. As with most Anobiids the prothorax (the first section of the thorax) hangs over the head when viewed from above. 

You can go onto PestWeb's Pest ID resource and compare some pictures. Look in the Pests / Pest ID which goes to the program and then use the search field for specific bugs. The wood infesting Anobiids that are most common along the Pacific Coast seem to be the Furniture Beetle. This is similar in general appearance to the Drugstore but it is gray rather than brown, a bit larger, and the prothorax is not as smooth in profile, but has an enlarged bump on top. You can see images of this in our Pest ID as well. The Anobiids that infest wood prefer relatively damp wood, so your locality in Washington should provide that for them, as does the climate in San Francisco where I have seen major issues with this beetle. Anything that can be done to lower the relative moisture level in the wood will help with the control and prevention. 

But, in your case, it has to begin with the ID to determine just what this is. There are plenty of native species of Anobiids out there too that may come to lights at night, but if you are finding them in numbers inside the home it suggests a source inside as well. Since these are in the kitchen, were I a betting man I'd go with Drugstore, and that doesn't necessarily make it all easy. This beetle has a very wide range of foods that it will infest, so essentially anything that was a plant and now is dry food could be infested. I even once saw a kitchen cutting board absolutely filled with the beetles that were feeding on impregnated greases and oils in the wood, so they do have strong enough jaws to penetrate some hard surfaces. 

I suggest examining the samples with good magnification and compare them with our images on PestWeb. 



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