Mezium affine is a species of beetle in the family Ptinidae. Its common names include shiny spider beetle, northern spider beetle, and hood spider beetle.[1] It occurs throughout the Northern Hemisphere, and it is an introduced species in Australia.[2]
This beetle is 1.5to long with a very convex oval body. The abdomen is reddish brown to black, and the legs, antennae, and other parts are cream-colored.[2] The head, thorax, and legs have a coating of scaly yellowish or gray hairs. The rounded body shape earned it the common name spider beetle. The larva is up to long and yellowish white in color with a brownish head. It is coated in yellowish hairs.[1]
The larvae infest stored food and other products. They are known to live on grain, spices, fish meal, dog biscuits, dried fruit,[2] dried meat, dried mushrooms, seeds, wool, hair, feathers, skins, book bindings, dead insects, feces, and sugar.[1] It can be found in libraries and museums, where it may damage specimens and collections.[1]