Spider beetles are closely related to furniture beetles. They look somewhat like spiders. The adults move quite slowly around on their long legs. There is a clear narrowing between the chest and the arched abdomen. Spider beetles often play dead when disturbed. Most of the species rarely use their wings and usually the beetles are brought from place to place with goods or packaging.
The newly hatched larvae are active, but once they have found a food source, they become obese, curved and almost motionless. The larvae can spin webs and are often protected by loosely spun cocoons. Spider beetles are not picky. They appear as waste eaters in especially pigeons’ nests, and indoors on poorly cleaned stocks and ceilings.
There are examples of spider beetles, more so than other insects, having found out how to use the plastic tubes embedded for electrical wires in walls as main ways in and out of buildings. Common for spider beetles is that they can survive at lower temperatures than other storage beetles and that their development is slow.