Pest Identification And Information

Pantry Pests

Many different pests make up what we call "Pantry Pests". Many of these pests are not exclusive to your pantry though, so their presence doesn't necessary mean the source is in your pantry but that's a good place to start. The best thing to do is to find the infested source and remove it.

In this document, we cover:

• Red and Confused Flour Beetle

• Sawtoothed and Merchant Grain Beetle

• Drugstore and Cigarette Beetle

• Indian Meal Moth

• Black Carpet Beetle

• Mediterranean Flour Moth

• Yellow and Dark Mealworm Beetle

Red Flour Beetle and Confused Flour Beetle

Biology:

Minimum Life Cycle: 23 days.
Distribution: Worldwide; on many products, secondary on whole grain; confused flour beetle more common in the north than red flour beetle.
Eggs - Up to 450 eggs per female laid on foodstuffs over several months.
Larvae - Prefer cereal embryos.
Adults - Can live for 18 months

Adult beetles of these two species have shiny, reddish brown bodies that are about 1/7 inch long, flattened, and oval. The small size of the confused flour beetle enables it to work its way inside many sealed containers.

The red and confused flour beetles are cosmopolitan pests of a wide range of grain, cereal, and other food products, but they prefer milled grain. They are very similar in appearance and can be most easily distinguished by examining the antennae: the antennae of the red flour beetle end abruptly in a three-segmented club, while the confused flour beetle's antennae gradually enlarge towards the tip, ending in a four-segmented club.

The confused flour beetle (CFB) is primarily a pest in northern states. The CFB adults do not fly.
The red flour beetle (RFB) is primarily a pest in southern states. The RFB adults are strong fliers.

HABITS:

These beetles have a very wide food range including cereals, grains, spices, grain products, shelled nuts, dried fruit, chocolate, drugs, peas, beans and other similar materials. The biology of these two species are very similar; their average life span is about 1 year, but some have been known to live almost 4 years.

The females lay their small, white eggs loosely in flour or other food material.

The eggs, which are coated with a sticky secretion, become covered with flour or meal and readily adhere to the sides of sacks, boxes, and other containers.

They hatch into small worm-like larvae that are slender, cylindrical in appearance. When fully grown, the larva is 3/16 inch long and white, tinged with yellow.

At this stage, it transforms into a small pupa. At first white, the pupa gradually changes to yellow and then brown, and shortly afterward transforms into a beetle.

In summer, the period from egg to adult averages about 6 weeks.

The adults are very active, especially in the evening hours. These insects produce a foul odor and taste in the food products that they infest.

Sawtoothed and Merchant Grain Beetle

Biology:
Minimum Life Cycle: 20 to 25 days.
Distribution: Cosmopolitan; important pest of many stored products, secondary pest of whole grain.
Eggs - Up to 400 per female laid loosely in the grain.
Larvae - Develop rapidly, particularly at high moisture contents (greater than 14 percent).
Adults - Can be long lived, up to three – four years.

They are slender, flat, brown beetles that are about 1/10 inch long.

Both beetles are similar in appearance, with six saw-like tooth projections on each side of the thorax (section between head and abdomen).

The adult beetles live an average of 6 to 10 months, but some individuals may live as long as 3 years.

The saw tooth beetle is found in warmer climates and does not fly. The merchant grain beetle flies.

The saw-toothed grain beetle has smaller eyes than the merchant grain beetle and a much larger area just behind the eyes.

HABITS:

In both larval and adult stages, these beetles feed on all food of plant origin, especially grain and grain products like flours, meals, cereals, dried meats, breakfast foods, stock and poultry feeds, coconut, nut meats, candies, and dried fruit; it is not uncommon to find these beetles infesting pet food, bird seed, and rodent bait.

They are small enough to very easily penetrate tiny cracks and crevices in packages food products.

The biology of both beetles is nearly identical and they are managed in the same manner so that it is not necessary to distinguish the two species.

The female beetle of both species drops her eggs loosely among the foodstuffs or tucks them away in a crevice in a kernel of grain.

Eggs are laid either singly or in small masses in crevices in the food supply, or may be laid freely in items such as flour or cereal.

When the small, slender, white eggs hatch, the emerging larvae crawl and feed on the foodstuff.

The larva nibble on finely divided food particles. It cannot feed on large particles such as whole grains.

They become full-grown in about 2 weeks during summer weather and then construct delicate cocoon-like coverings by joining together small grains or fragments of foodstuffs with a sticky secretion.

Within this cell, the larva changes to the pupal stage.

Drugstore Beetle and Cigarette Beetle

Biology:
They closely resemble one another, but the cigarette beetle is the more common of the two. Both beetles have a "hump-backed" appearance.

Both beetles are about 1/8 inch long, cylindrical, and uniformly light brown.

The wing covers of the drugstore beetle have longitudinal grooves, while those of the cigarette beetle are smooth.

Also the body hairs of the cigarette beetles are considerably longer, giving it a more "fuzzy" appearance.

The small, yellowish white grubs are covered with long, silky, yellowish brown hairs and are about l/6 inch long when fully grown.

The period from egg to adult is about 6 weeks.

HABITS:

The cigarette beetle feeds on cured tobacco, cigarettes, and cigars. It may be a serious pest of items such as books, flax, cottonseed meal, cereals, and cereal products, animal products, wool, rice, ginger, pepper, paprika, dried fish, seeds, and dried plants. In the home this beetle is most commonly found in pet foods, cereals, nuts, and candy.

The cigarette beetle lays its eggs in the food substance.

The pupae are within a closed cell composed of small particles of the food substance cemented together with a secretion of the larvae.

The drugstore beetle is a very general feeder, attacking a great variety of stored foods, seeds, pet foods, spices, and flour mixes. One of the more commonly infested materials is nibbled dog food.

It gets its name from its habit of feeding on almost all drugs found in pharmacies.

In the home, however, the most common food materials to find this beetle infesting are pet foods, drugs, and cereals.

The drugstore beetle lays eggs in almost any dry, organic substance.

After hatching, the small, white grubs tunnel through these substances and, when full grown, pupate in small cocoons. The entire life cycle may take place in less than 2 months.

Indian Meal Moth

[For More Info - See Seperate Document]

Biology:
Minimum Life Cycle: 26 days.
Distribution: Cereals, dry pet food, ground nuts, and dried fruits.
Eggs - 100 to 300 eggs laid on or near produce.
Larvae - Spin threads as they feed forming webs; particularly resistant to insecticide treatment. Can be seen crawling away from foodstuffs to pupate
Pupae – Form on ceiling/wall juncture, under shelves etc.
Adults - Non feeding; short lived.

Adults of Indian meal moths have a wingspan of about 3/4" when at rest, the wings are folded together-held tightly together by the body. The wing is a blend of two colors: front half of the wings-pale gray-pale tan, bottom half of the wings: a rust-bronze color

Larvae size: is 1/2", a dirty white-off white color, it can have green or pink hues.

Indian meal moths can take from 25-135 days for an egg-egg development cycle to occur.

HABITS:

Indianmeal Moth (Plodia interpunctella). This moth is distributed in a wide range of climates, and is found in many types of foods and processing and storage facilities. larvae are general feeders and the adults do not feed. The larvae produce a dense webbing.

Indian Meal Moths are probably the most common pantry pest found in kitchens and pantries in North America

They are nocturnal, flying a night...if disturbed during the flying, they will zig zag. They rest during the day in dark places.

They lay their eggs in food stuffs like: grains, grain products, dried food, dried fruit, powder milk, seeds, candy, chocolates, and specially dry pet foods.

The larva is what does the damage-feeding on these different food items, forming an extensive web type of substance over the food items that they infest.

Abundant webbing in infested materials is characteristic of infestations by the Indian meal moth. Its larvae are often found far from infested foods because they usually crawl away from their foods to construct silken cocoons in which to pupate.

Black Carpet Beetle

Biology:
Minimum Life Cycle: Nine months.
Distribution: Cosmopolitan; not injurious to stored grain products.
Larvae - Found in cracks or walls where foodstuffs accumulate.
Adults - Emerge in spring and early summer to lay eggs.

They lay eggs either indoors or outdoors, beginning 4 to 8 days after the adult emerges. Each female lays approximately 50 eggs over a period of about 3 weeks, after which she dies.

Body color varies from a light brown to almost black.

Black carpet beetle larvae may live as short as 9 months to as long as 3 years, depending on their diet and environmental conditions.

HABITS:

The black carpet beetle, a dermestid beetle, includes several similar species that may all be referred to as black carpet beetles. They usually have an annual life cycle. The adults feed only on flower nectar, pollen, and free water, while the larvae usually feed on wool, leather, silk, fur, and other animal products. Several species of these insects are found worldwide, but more commonly in temperate areas. The adult females produce a sex pheromone useful in detecting and monitoring the insect.

This as the most abundant and widespread of the carpet beetles and is the species which causes the greatest damage to fabrics and other keratin containing articles throughout most of the United States. Adults are shiny black with brownish legs, and grow to a length of 1/8- to 3/ 16-inch. They are frequently found outdoors in flowers and are most numerous in the spring and early summer. Carpet beetle larvae are frequently pests of insect collections, dead ladybugs in wall voids, and other museum specimens.

Since they are attracted to flowers, and in the spring of the year the adult Black Carpet Beetle may fly into the house.

Indoors, these eggs are deposited in accumulations of lint, in air ducts, underneath baseboards and other similar places. Eggs hatch in 6 to 11 days in warm weather.

They can develop under a wide range of temperature and humidity conditions, and are much less susceptible to environmental changes than are clothes moths.

Larvae may grow to 1/2-inch long over a series of 5 to 11 molts. They tend to avoid lighted areas, so are found most frequently in the lower parts of clothes closets, rolled up or wrapped into woolen materials, at the edge of carpeting under baseboards, or inside upholstered furniture.

Mature larvae can wander rather widely, so may be found anywhere in a building. It is not at all unusual to find them in a bathtub, kitchen sink, or even crawling on walls and ceilings.

Black carpet beetle larvae are general feeders, feeding on dead animal materials, hair, fur, hides
and horns, as well as the usual woolen products. They tend to be surface feeders on wool, usually eating the nap from fabric and leaving the base threads relatively unaffected.

They also can feed on many plant materials such as cereals, stored grain or nuts.

However, they are quite capable of eating large, irregular holes through any suitable food material. In fur, hairs are cut at the base with no injury to the hide. The hair then readily drops out leaving a bare appearance to the hide.

Black carpet beetle larvae frequently burrow through containers to obtain food, leaving small openings through which other insects may enter to cause additional damage.

Cast skins and frass in the form of minute, irregular pellets are frequently found on infested fabrics.

Mediterranean Flour Moth

Biology:
Minimum Life Cycle: One to six months.
Distribution: Temperate areas; attacks cereal products particularly flour.
Eggs - Up to 300 eggs laid on or near produce.
Larvae - Particularly favor flour dust; webbing from heavy infestations can choke machinery.
Pupae - Form in the produce from overwintered larvae.
Adults - Non feeding; short lived.

The Mediterranean Flour Moth is somewhat larger than the Indian Meal Moth

The adult moth is a pale-gray color and from one-forth to one-half inch long, with a wingspread of slightly less than one inch.

The wings are marked with two indistinct, black zigzag lines.

The hind wings are a dirty white.

During very warm weather, the Mediterranean flour moth may complete its life cycle (egg to adult) in five to seven weeks.

HABITS:

Development and damage is similar to the Indian meal moth, except the larvae live and feed in small silken tubes they spin. Although flour is the favorite food, grains, bran, breakfast foods and pollen in beehives are also attacked. The life cycle takes about 10 weeks. The webbing and matting of the larvae often cause the greatest amount of damage by this insect, whether it is contaminating foods in the home or clogging industrial machinery.

This moth is easily recognized by its characteristic pose when resting. When at rest, the moth extends the forelegs which raises the head and gives the body a sloping appearance.

None of the other house moths have this characteristic pose.

The female moth lays from 116 to 678 small white eggs in accumulations of flour, meal, waste grain, nuts,chocolate,beans, dried fruits and other food sources.

Commonly, the eggs are attached to the food.

Within a few days (three days at eighty to ninety degrees F) the eggs hatch into small whitish or pinkish larvae, with a very hard and dark colored head and small black spots on the body, that immediately begin to spin silken tubes.

The larvae remain within the tubes until fully mature, which takes approximately forty days.

When fully grown, the larvae will leave the immediate area where they were feeding and wander about in search of a location to spin silken cocoons.

Within the cocoons, they transform into reddish-brown pupae.

After eight to twelve days the adult moths emerge.

Yellow and Dark Mealworm Beetle

Biology:
Minimum Life Cycle: One year.
Distribution: Cosmopolitan in the United States.
Eggs - Laid in grain or food products.
Larvae - Feed in grain.
Adults - Feed in grain.

HABITS:

Yellow and Dark Mealworm (Tenebrio molitor). The yellow and dark mealworms are not considered serious pests because of their long life cycle (usually one year). The mealworm larvae and adult beetles both feed on whole grain and grain products. The eggs are sticky and are deposited in the loose food particles. The larvae are active crawlers and the adults are good fliers. The adults have aggregation pheromones and usually prefer dark areas.