Warehouse beetle (Trogoderma variabile)
Type of pest: Primary pest, secondary pest.
Distribution: Worldwide, especially warm temperatures and Mediterranean regions.
Identification: Adults are 2 – 3.5 mm, oval, with hairy elytra with three transverse wavy pale brown lines. The antennal club has three to eight segments, joined symmetrically. Larvae: eruciform, oval, with bands of hair. Tufts at the rear do not converge over the abdomen tip.
Similar species: Anthrenus, Anthrenocerus, other Trogoderma – identification only reliable by examination of genitalia and internal structures.
Life cycle: Optimal development conditions in 30 days at 30 Celsius. Eggs are laid amongst the commodity. The larvae are mobile, cast skins are left in infested material, and survive without food for years. Adults are short-lived, do not feed on the commodity and can fly.
Commodities infested: Warehouse beetles are voracious feeders. They have been reported from seeds of all kinds, dead insects and animals, cereal products, candy cocoa, corn, corn meal, dog food, fish meal, flour, oatmeal, milk powder, spaghetti, spices, peas, wheat, barley, and pollen. In grain they cannot feed on whole grain, but can feed on broken kernels that are usually present. A notable feature of warehouse beetle infestations is the accumulation of skins shed by the larvae, which may molt up to ten times before pupation. Hairs shed by larvae may cause asthma, skin or gastric problems.
Treatment: Controlled Atmosphere for infestation in product
Treatment: Heat Treatment for infestation in buildings
Warehouse beetle (Trogoderma variabile)Tropical warehouse moth (Ephestia cautella)Tobacco moth (Ephestia elutella)Spider beetle (Ptinus fur L.)Sawtoothed grain beetle (Oryzaephilus surinamensis)Rust red flour beetle (Tribolium castaneum)Rice weevil (Sitophilus oryzae)Mites (Astigmata)Mercant beetle (Oryzaephilus mercator)Mediterranean flour moth (Ephestia kuehniella)Mealworm beelte (Tenebrio molitor)Maize weevil (Sitophilus zeamais)Lesser grain borer (Rhyzopertha dominica)Larger grain borer (Prostephanus truncatus)Khapra beetle (Trogoderma granarium)Indian meal moth (Plodia Interpunctella)Grain weevil (Sitophilus granarius)Flour mite (Acarus siro L.)Flat grain beetle (Cryptolestes spp.)Fruit fly or vinegar fly (Drosophilidae)Confused flour beetle (Tribolium confusum)CockroachesBruchidaeCoffee bean beetle (Areacerus fasciculatus)Broad horned flour beetle (Gnatocerus cornutus)Drugstore beetle (Stegobium paniceum)Cigarette beetle (Lasioderma serricorne)Bean beetle (Acanthoscelides obtectus)Australian spider beetle (Ptinus tectus)Almond moth (Cadra cautella)