Tenebroides mauritanicus (Linnaeus)


Primary pest; Grain feeder
Order: Coleoptera
Family: Trogossitidae
Acronym: TMA


  • Adults are shiny black to brown beetles that range in size from 6 to 19 mm.
  • Larvae are whitish in colour with a black head, thoracic shield and urogomphi.
  • Larvae reach a length of up to 19 mm.
  • Larvae are active in the food.

Similar species

Commodities affected

  • Grains, nuts, flour and other grain products, dried fruit, spices

Signs of infestation

  • No specific signs, unless holes are found in surrounding structures, indicating presence of larvae


  • Damage is not distinguishable.
  • Cadelles prefer to feed on the germ, leaving the remainder of kernel untouched.

How to control

Geographical range

  • Is distributed worldwide
  • Is distributed across Canada through all provinces

Where found

  • Is a common pest in flour mills, granaries, ships, elevators, warehouses and stores
  • May also be a pest in farm-stored grain and homes
  • Is usually associated with aged residues
  • Larvae can burrow into wooden structures or plastered walls, causing structural damage that provides hiding places for other stored-product pests.

Life history

  • Females lay eggs in batches of 10 to 60 in the food supply.
  •  Cadelles prey on other stored-product insects.
  • Larvae and adults will also eat holes in flour sacks, food cartons and bolting cloth.


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