Almond moth
Cadra cautella (Walker)

Order: Lepidoptera
Family: Pyralidae
Acronym: CCA

Ecology

The almond moth is found worldwide. It is a scavenger. It is found in mills, processing facilities, warehouses and households. The almond month is found more often in heated structures than in non-heated structures. It feeds on grain, cereal products, oilseeds and dried plant products, like nuts, fruit and tobacco. However, it is more of a pest of nuts and dried fruits than it is of grains and cereals. During the day, the adult moth can be seen resting on walls and other surfaces. It flies mostly at dusk and dawn.

Damage

The almond moth infests stored products. Damage is not distinct and is caused by larval feeding. When feeding on whole grains the larva prefers to feed on the germ and bran. The larva burrows into food and creates silk tunnels in which it will be concealed while feeding. It produces silk webbing when it feeds and binds the surface of a grain bulk together. Large larva can burrow through packing. A sign of infestation in the product is contamination with silk webbing, frass, cast skins, pupal cases and adult remains.

Life history

The adult almond moth has a wing span of 19 mm. The body is 7.5 – 10 mm long. The labial palps are upturned. The forewings are grey to dusty brown. There is a dark straight band across the forewing, which is paler on the inner edge. The hind wing is light grey to beige and has a fringe of hairs on the wing margin. Both the forewings and hind wings are rounded at the apex. The adult does not feed on the commodity. The adult can fly.

Breeding conditions are temperatures between 17°C - 37°C and humidity greater than 20%. It breeds rapidly in conditions with high heat and humidity. The female lays 150 - 200 eggs loosely and randomly on a food source.

The larva is white to pink in colour and has a distinctive brown head. It can grow to 12.7 mm in length. The larva is active. Each body segment has two black spots, which run in parallel lines down the back. If the temperature is 30°C and the humidity is 80%, the larva can complete its development in 26 days. When the larva is mature, it will actively leave the food source and search for a site in which to pupate. The larva pupates in a silk cocoon. The larva can enter diapause if the conditions are unfavorable for development. Several generations a year can be produced.

Control

Controlling insect infestations

Images

Almond moth: larva, pupa and adult