Warehouse beetle
Trogoderma variabile Ballion

Classification

Secondary pest: Grain feeder and scavenger
Order: Coleoptera
Family: Dermestidae
Acronym: TVA

Description

  • Adults are oval and 2.0 to 4.6 mm in length with females being larger than males.
  • Elytra are generally dark with different coloured contrasting bands that vary from brown to red.
  • Adults are generally is dark brown with 3 lighter brown or reddish bands.
  • Larvae are whitish yellow initially and darken with age.
  • Larvae are typical dermestid larvae with tufts of dense hairs on the posterior segments.

Similar species

  • Other Trogoderma species
  • Anthrenus species
  • Anthrenocerus species

Commodities affected

  • Stored seeds, legumes, canola, nuts, animal feed, barley, wheat, pollen

Signs of infestation

  • Presence of cast larval skins is the most readily identifiable sign of infestation

Damage

  • Warehouse beetle is a generalist feeder that does not cause distinctive damage
  • Larvae cause damage when they feed. Adults feed on nectar and pollen
  • Larvae damage all parts of the seed except for the shell
  • Larvae can infest bagged grain and processed, packaged food

Control

Geographic range

  • Is distributed worldwide and across Canada

Where found

  • Is found in flour and feed mills, processing plants, feed warehouses, dried milk factories and in stored grain
  • Is a pest in alfalfa leafcutter bee nests

Life history

  • Females lay eggs randomly on dried plant or animal material.
  • Development time ranges from 30 to 45 days, on average.
  • Larvae are able to enter diapause (dormant state) when developmental conditions are unsuitable.

Images

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Did you know?

The warehouse beetle is the second most important Trogoderma species world wide.