Meal moth
Pyralis farinalis (L.)

Classification

Secondary pest: Grain feeder
Order: Lepidoptera
Family: Pyralidae
Acronym: PFA

Description

  • Adults are relatively large with a wingspan of 22 to 30 mm and a body length of 7.5 to 15 mm.
  • Forewing is distinctly patterned with a pale or tan centre bordered by a reddish base and apex. The centre is bordered by a wavy white line.
  • Hhind-wing is also patterned.
  • Larvae are whitish in colour with a dark head capsule and prothoracic segment.
  • Larvae do not haveblack spots on their bodies.

Similar species

  • None

Commodities affected

  • Wheat, barley, oats, corn, peas, beans, flour, peanuts, dried fruit, potatoes in storage, mixed feed, processed cereals, hay (alfalfa and clover)

Signs of infestation

  • Contamination with silk webbing
  • Presence of frass (excrement), cast skins, pupal cases, adult remains

Damage

  • Damage is caused by larval feeding and is not distinctive.
  • Larvae produce silk webbing that can bind the food surface.
  • Irregular holes are chewed into attacked material.

How to control

Geographic range

  • Is found worldwide but is more common in temperate regions
  • Is found across Canada

Where found

  • Is able to survive winters in unheated granaries
  • Is found in grain elevators, mills, processing facilities, warehouses, grain ships, households
  • Is a minor pest of coarsely ground cereal products
  • Is most abundant in mouldy grain, decaying cereals and cereal products that have a high moisture content
  • May be thought of as an indicator of poor sanitation

Life history

  • Females lay ggs randomly amongst the food source.
  • Larvae actively leave commodity to search for a site for pupation that occurs in a silken cocoon.

Images

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