Ptinus fur, the white marked spider beetle, is a species of spider beetle in the genus Ptinus (family Ptinidae), with a nearly cosmopolitan distribution.[1]
Adults are morphologically similar to other spider beetle species, notably the hairy spider beetle (Ptinus villiger).[2] It is red-brown with yellow hairs, and measures 2mm4.3mm in length. The prothorax is densely covered with pale hairs, while the elytra bear some patches of white scales.[1]
It is a pest of stored foods, with a worldwide distribution, where it may be identified by leaving webbed, granular materials on the stored products. Ptinus fur adults feed on dried and decaying animal and vegetable material.[3] It has also been identified as a pest in museums, damaging stored collections.
It has been found in the nests of birds, notably the Sand Martin.[4]
The optimum temperature for rapid development of Ptinus fur is about 23 °C, at which temperature it completes its development in a mean period of 132 days.[5] Larvae of P. fur normally moult three times at 23°Cm but some have an extra moult.
Well-defined diapause as mature larvae in cocoons occurs at low temperatures in some individuals of Ptinus fur: at 23 °C this lasts about 220 days after normal larvae have pupated; at 20 °C the period lasts about 280 days.
Adult beetles live for several months.