Scientific Name: Plodia interpunctella
The Indianmeal Moth has forewings which are reddish brown in colour with a copper sheen, their hind wings tend to be paler. Adults have a 16-20 mm wingspan. Larvae tend to be off-white, pink or brown depending on food and can travel large distances within a kitchen for pupation.
A native of America, the Indiameal Moth is now a cosmopolitan species.
It is the most common pest of stored products in household and grocery stores. Usually feed on grain products, seeds, dried fruit, dog food, spices, etc. One generation is usually produced but in warm conditions, adults will be present throughout the year and may produce 4-6 generations.
Most active from dusk until dawn, it rests during the day. This species is a particular pest of flour mills.
Mating takes place immediately after the adults emerge. Up to 350 eggs are laid and these may be stuck to various foods by a sticky secretion. The eggs hatch in 4-28days and the larvae spin silken tubes in which they live. After 3-5 moults the larvae are fully grown and 15-19mm long.
Larvae present a more serious problem, as it is their feeding and excretions that contaminate the produce. The adults do not feed.
The larvae produce copious amounts of silk which contaminates grains but this larval webbing also causes serious blockages in provender mills. The larvae eat holes in sifting silks and may also reach mill’s finished products.
The webbing may also cause condensation which leads to damaging molds.