Whitemarked spider beetle
Ptinus fur (L.)


Secondary pest: Grain feeder and scavenger
Order: Coleoptera
Family: Anobiidae
Acronym: PTI


  • Adults are morphologically similar to other spider beetle species, notably the hairy spider beetle (Ptinus villiger).
  • Adults can be separated from other spider beetles by examination of the setae on the elytra. On P. fur the setae on the elytra are equal in length; this is not the case in P. villiger.
  • Larvae are grub like and white in colour.

Similar species

Commodities affected

  • Affect flour, corn meal, bran, seeds, grain, pepper, cocoa, sugar
  • Is a serious pest of zoological collections
  • Is reported to feed on grain dust in terminal elevators

Signs of infestation

  • Presence of webbed, granular material
  • Irregular damage (chewed holes) to endosperm


  • Damage results from accumulation of silk and granular material


Geographic range

  • Is found worldwide and across Canada
  • Is most abundant in British Columbia

Where found

  • Feeds on a variety of dried and decaying animal and vegetable material
  • Requires high humidity to effectively reproduce
  • Is found mainly in warehouses and dwellings
  • Is less frequently found in museums, granaries and grain elevators

Life history

  • Females lay eggs in cracks and crevices around the food supply.
  • Larvae may be somewhat gregarious and form feeding clusters of 3 to 4 individuals amongst several kernels glued together.
  • Larvae secrete a silky substance to form a puparia.


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