| Biscuit and Cigarette Beetle | Booklice | Flour Beetle | Grain Beetles | Grain and Rice Weevil | Indian Meal Moth | Mill Moth | Brown House Moth |
Biscuit and Cigarette Beetle |
| Appearance and Significance |
Adults are 2–3mm in length. Covered in fine hairs all over the body. The wing cases have ridges with indentations.
Very common insect pest in dried foods, they prefer hard materials for example, biscuits, dry bread, spices, soup powders.
Larva are active in early stages of development and are seldom seen often inside food. They are able to detoxify some poisonous substances.
Emergence holes of adults are similar to woodworm (same family). They may live in a small packet until all food is gone. |
| Lifecycle |
| Life cycle approximately 200 days at 17°C, 70 days at 28°C. Adults live for 13 to 65 days. |
| Habits |
| Adults will often fly spreading to all parts of the trade. Adults do not feed, however adults and larvae chew most packaging. |
| Prevention |
| Careful stock inspection. Date and code rotation is important. Always check product at back of shelving. The use of sticky tapes can be helpful in detection. Structural spray may help in an early infestation. Fumigation is the only resort of large quantities, otherwise product must be destroyed. |
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Booklice (Liposcelis bostrychophila) (Lepinotus patruelis) |
Appearance and significance |
Adult size varies according to species. 1–2 mm long. Pale yellow–brown todark brown in colour.
Nymphs are very small, and often appear transparent. There are no larvalstages.
Ever-present, very primitive insect. Generally tend to live out doors in damp leaves and litter. Indoors in damp areas, they prefer moulds growing on the surface of foodstuffs (and on non-edible materials such as cardboard and paper) may also support booklouse populations. |
Lifecycle |
Liposcelis bostrychophila prefers high temperatures 25–30°C.
Lepinotus patruelis will breed at 5–15°C. |
Habits |
Liposcelis bostrychophila is common in homes.
Lepinotus patruelis is common in factories and on pallets.
Rapid breeding in high humidity conditions which promote “flash infestations”. The movement is more obvious than the insect, as they tend to blend with most foods. |
Prevention |
Susceptible to reduced humidity and thorough dry cleaning. Trapping is useful for detection purposes.
Structural sprays can also be useful. Ensure pallets are dry before use. |
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Flour Beetle (Tribolium confusum) |
Appearance and Significance |
 Adults are 3–4mm in length. Eyes are wider apart (as seen from the underside) than T. castaneum. Antennae broaden gradually to the tip. Red–brown in colour.
Endemic in feed and flour mills, cereal products, nuts. Generally a tropical species, commonly imported on wider range of stored products, requires warmth. Taint foods, pungent/sour secretion. Flour ‘filth test’ contamination.
Larva are whitish to yellow–brown, 1 – 5mm long. 3 pairs of legs and active. Moults 7–8 times. Preference for clean flour. Pupates in foodstuffs. |
Lifecycle |
| About 20 days at 35°C, 45 days at 25°C. Adults may live for up to 6 months. |
Habits |
 Seldom seethe damage; heavy infestation results in a distinctsmell and tainting. Trails in dust. Favours the seams/flaps of sacks/cartons and beneath machines and behing skirting strips.Can fly but rarely does so. Feeds on flour and cereal products |
Prevention |
| In-depth inspection, bait bags, sticky pheromone traps. Often hide from light. Check known places, dead spaces. Spot treat machinery, structural spraying. Contaminated foods may need destroying. |
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Grain Beetles (Oryzaephilus mercator) |
Appearance and Significance |
 Adults are 2.5–3mm in length. 6 saw–like projections on each side of the wing case. Short length of head behind the eyes.
Endemic primary pest of grain, cereal products, and nuts. Serious heating/spoilage in bulks; easy invasion of most packaging. Product contamination.
Larva are yellow to brown with a black head. |
Lifecycle |
| Optimum conditions are 30–33°C. Cannot tolerate low temperatures. |
Habits |
| Difficult to detect. Grain heats up with heavy infestation. Larvae seldom seen, adults very active above 18°C. A particular pest of dried fruit and chocolate. |
Prevention |
| Use traps, keep temperature below 12. Prophylactic or control admixture, fumigation as a last resort. Store hygiene. |
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Grain and Rice Weevil (Sitophilus granaries) |
Appearance and Significance |
Adults are 2–3mm in length. Oval indentations in thorax. Black-brown colour. Cannot fly (fused elytra).
Worldwide pest of grain, pasta, rice and hard products. Serious physical damage, heating in bags and bulks. Chew packaging material, damage sack fibres.
Larva are usually hidden within grain where it pupates. Legless. Prefers wheat and rye but will infest other cereals. |
Lifecycle |
| 30 days at 30°C. Normally 8–16 weeks. Can develop at 11°C. |
Habits |
| A pest of grain. Newly emerged adults leave a characteristic emergence hole in the grain.
Larvae hidden inside hard foods. Infestation only visible in adult stage. Hollowed out grains, bore dust, sound of chewing larvae sometimes clear. Exit holes in packaging. |
Prevention |
| Traps in bags and bulk grain. Careful stock inspection of food; maybe sticky traps. Prophylactic spray or fumigation of grain. Warehouse structure spray. Stock rotation important. Destroy infested products. |
| Top5 |
|
Indian Meal Moth (Plodia interpunctella) |
Appearance and Significance |
Adults are 7—9mm in length, wingspan 15—20mm. First third of forewings are a pale buff colour. Remainder of the wings are reddish brown.
Very common and wide spread pest of stored foods, groundnuts, dried fruit and manufactured foods. Larval contaminated contamination is the main problem. Chew through most packaging.
Larva are yellowish-white, reddish or greenish (depending on diet) with a brown head. |
Lifecycle |
| 35 days at 2°C. Much longer at lower temperatures or when feeding on low nutrition foods. |
Habits |
| Feeds on nuts, dried fruit and grain (maize). Adults not always seen. Larvae yellow-white; produce silk , web food particles together; leave tell tale frass (droppings) – small white particles. |
Prevention |
| Not susceptible to normal hygiene. Use in-depth raw material and warehousing surveys and pheromone traps. Fumigation may be last resort for raw materials (not prophylactic). |
| Top5 |
Mill Moth (Ephestia kuehniella) |
Appearance and Significance |
Adult are 7—9mm in length with a wing span 15—20mm. Black zig zag pattern across the wings which are grey.
The main moth pest in UK and European flour mills. Also in the Middle East and sub-tropics. Silk blockages stop mills and machinery. Also a pest in animal feed mills, bakeries and some food stores.
Larva are pinkish or greenish tinge depending on food eaten. Brown head. Lives within a silken tube. |
Lifecycle |
| 152 days at 17°C, 42 days at 30°C. Prolific silk spinner. Adults live about 2 weeks. |
Habits |
Rarely attacks commodities other than flour. Adults tend to rest during the day and fly at dusk.
Adults may be seen resting on walls. Larvae whitish with black speckles. Characteristic Larval silk blocks chutes, spouts and worms. Webbing often the only sign in packaged products in stores. |
Prevention |
| In-depth cleaning of mill machinery may control moths; annual methyl bromide fumigation more sure to eliminate infestation. Use pheromone traps for early detection. For stores /shops use traps and destroy goods. |
| Top5 |
Brown House Moth (Hofmannophila pseudospretella) |
Appearance and Significance |
Adult are 8–14 mm long. Dark brown forewings each with three or four black spots.
An important poor hygiene pest. In undisturbed areas and residues. Likes animal protein: dead insects and rodents. Contaminates/ damages products and packaging.
Larva are up to 20 mm long. Dirty white with a brown head. 1st thoracic segment is a chestnut colour.
Pupa are 15 to 20 mm long in a silk cocoon. |
Lifecycle |
| Normally one generation per year. |
Habits |
Larva may wander considerable distances prior to pupation. Generally regarded as a scavenger.
Adults rest on walls in darker places. White larvae usually hidden in food in silky tub, but whitish frass (droppings) visible. Older larvae fleshy. Tough silk cocoon often in cracks and on walls behind sacks/pallets.
Adults may be seen resting on walls. Larvae whitish with black speckles. Characteristic Larval silk blocks chutes, spouts and worms. Webbing often the only sign in packaged products in stores. |
Prevention |
| Thorough hygiene most important. Remove dead rodent bodies. Clear birds’ nesting. Inspect packaging and product stocks; date order rotation. Wall/floor angle cleaning and spraying for larvae. |
| Top5 |
