What characteristic defines Anobiid (Furniture and Deathwatch) beetles?

Anobiid beetles, also known as furniture and deathwatch beetles, are characterized by the absence of an antennal club. This feature differentiates them from many other beetle families that have a distinct clubbed antenna structure. The absence of an antennal club is important for identification purposes, as it helps entomologists and pest control professionals accurately classify these beetles.

In contrast, visible heads from above, evidence of frass, and large size do not accurately define Anobiid beetles. While some beetles may have visible heads or produce frass, these traits are not unique to the Anobiidae family. Additionally, Anobiid beetles are generally small to medium-sized, so size alone does not serve as a distinguishing characteristic. Understanding these specific features is crucial for anyone studying or working in pest management and entomology.