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Black Widow Spider

Article author: Mike Merchant
Most recently reviewed by: Pat Porter (2018)

Common Name(s): Black Widow Spider

Description

Shiny, black spider with globular abdomen, usually with two reddish, triangular shaped markings on the underside of the abdomen. These markings often are joined to form an hourglass shape. The red markings vary among individuals and may look merely like spots, or a row of red spots may occur on the top of the abdomen. Immature spiders have white, yellow, orange or red markings on the top of the abdomen. The egg sac is free (not attached to flat surfaces). It is tan with a tough papery texture and is spherical with a nipple on the tip.

Origin and Distribution

Four structure-infesting species of widow spiders are found in all 48 states in the continental U.S.

Habitat & Hosts

They are not common indoors, but they are found in undisturbed sites such as basements and storage areas and prefer cluttered areas. Webs are built between stationary objects and walls. Outdoors, they prefer protected places near the ground, such as under stones, pieces of wood or brick piles or in rodent burrows and hollow tree stumps. Their favorite places are barns, sheds, meter boxes, brick veneer, barrels and woodpiles.

Widows tend to be clumsy out of their web and bites usually only occur if a hand is stuck in the web, or if a spider is inadvertently grabbed while cleaning areas like a garage or shed. Black widows come out at night and hunt in their cobweb-like webs. Since black widows don’t move easily, they wait for prey to come to them.

Life Cycle

Egg, spiderling (nymph) and adult. Lay eggs in a loosely woven cup of silk

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

Using a flashlight, inspect corners, along edges, by light fixtures and windows as well as under cabinets and furniture. If moving any objects for inspections, wear gloves to avoid any bites. Outside inspect along the foundation of the structure, especially near areas with landscaping. Check electrical boxes, irrigation boxes and other protected areas. Use glueboards/ sticky traps in suspected areas of infestation to monitor spider populations.

Interior or exterior insecticidal sprays are generally ineffective at reducing spider populations, but may provide some repellency.

Insecticidal dusts can be used in low traffic areas such as boiler rooms, crawl spaces, and voids for long residual control of spiders.

Related Publications

https://citybugs.tamu.edu/factsheets/biting-stinging/others/ent-3003/

https://citybugs.tamu.edu/factsheets/biting-stinging/others/

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Bed bugs

Article author: Mike Merchant, Robert Puckett
Most recently reviewed by: Pat Porter & Katelyn Kesheimer (2018)

Common Name(s): bed bug, bedbug

Description

Bed bugs are small, brownish, flattened insects that feed solely on the blood of animals. The common bed bug, Cimex lectularius, is the species most adapted to living with humans. It has done so since ancient times.

Adult bed bugs are about 1/4 inch long and reddish brown, with oval, flattened bodies. They are sometimes mistaken for ticks or cockroaches. The immatures (nymphs) resemble the adults, but are smaller and lighter in color. The youngest nymphs are approximately pinhead size and visible to the naked eye. Bed bugs do not have wings and do not fly, but can move quickly over floors, walls, ceilings and other surfaces.

BEd bug on dime

Bed bug on dime, taken by Pat Porter

Origin and Distribution

Bed bugs prefer to hide close to where they feed. However if necessary, they will crawl quite a ways to obtain a blood meal. Initial infestations tend to be around beds, but the bugs eventually may become scattered throughout a room, occupying any crevice or protected location. They also can spread to adjacent rooms or apartments. This can be especially problematic on college campuses, hotels and anywhere multi-housing scenarios occur. For this reason, control must be comprehensive and pest management professionals must think 3-dimensionally.

Habitat & Hosts

Bed bugs feed mostly at night, by piercing the skin of people as they sleep. However, if they are very hungry and if the light is dim, they will feed during the day. When bed bugs are not feeding, they spend their time in large, dense aggregations that consist of all life stages from eggs to adult. They use chemical communication to locate each other in these groups that are typically in flat, dark spaces.

When bed bugs bite, they inject a fluid into the skin that assists them in obtaining blood. Often, but not always, the fluid causes the skin to become irritated, inflamed and to itch. Elongated, spindle shaped welts can develop as a result of the bite. If the bites are on the limbs (arms or legs), these welts will be aligned with the long axis of the limb. This elongated, spindle shape can distinguish the welts from those resulting from mosquito or flea bites. In some cases, it may take several days for the reaction to occur.

If its feeding is undisturbed, a full grown bed bug becomes engorged with blood in 3 to 15 minutes. It then crawls back to its hiding place, where it remains for several days digesting its meal. When hunger returns, the bug emerges from hiding and seeks another meal of blood.

Life Cycle

The three life stages are egg, nymph and adult. Under favorable conditions of temperature (above 70° F) and regular feeding, female bed bugs will lay about 200 eggs during their lifetime at the rate of 3 or 4 per day. Eggs are coated with a sticky substance, causing them to adhere to objects on which they are deposited. The eggs hatch in 6 to 17 days and the nymphs begin to feed on blood immediately.

After 5 molts, bed bugs reach maturity. However, bed bugs must obtain a blood meal before each molt and females must also feed before laying eggs. There may be 3 or more generations a year. Environmental factors and the availability of food will cause considerable variation in the developmental rate of all stages of growth. Young and old bed bugs may live for several weeks to several months without feeding, depending upon the temperature.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

To control bed bugs in homes, locate their hiding places such as described above and treat with an insecticide approved for this use. Select a product whose label includes specific directions for bed bug control. Spray or dust beds (slats, springs and frame) and other hiding places about the room.

Because it is impossible to penetrate all hiding places, control is usually not immediate. A few living bugs may be seen for a week to 10 days after application. After 10 days, a second application, equal to the first is necessary to kill the just hatching nymphs. The pesticides used for bedbug control have a short residual life and so this second application is always needed. For heavily infested areas, it is recommended that a commercial pest control operator be consulted to control the infestation.

Always read and follow carefully the instructions on the container label.

Related Publications

Bed Bugs – Insects in the City

Bed bugs: Do-it-yourself control options – Insects in the City

 

 

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Angoumois Grain Moth

Article author: John Jackman
Most recently reviewed by: Pat Porter (2018)

Common Name(s): Angoumois Grain Moth, Grain moth

Description

Angoumois grain moths are occasionally found as pantry pests in homes, but they can be serious pests in commercial grain storage. Adult moths are a buff, tan or golden color and about 1/3 inch long. The wing span is 1/2 inch, rear edges of wings are fringed. Larvae are white with a yellowish to brown head and dark reddish-brown mouthparts. Larvae bore into kernels of cereal grains, pupate and emerge through a hole cut on the outer surface of the kernel.

Origin and Distribution

Grain storage, warehouses, bins, and pantries. Larvae feed on many types of whole grains. They prefer damp grain over dry grain.

Habitat & Hosts

They feed on stored grain, especially whole corn. The larvae require whole kernels or caked material for development. They bore into the kernel, pupate and emerge through a hole cut on the outer surface of the kernel. They are active at low temperatures and prefer barley, rye, corn, oats, rice and various seeds.

Life Cycle

Angoumois grain moth has a complete life cycle; egg, larva, pupa and adult, and it takes about about 5 weeks to complete development.  Adults can fly and are attracted to lights.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

In commercial/agricultural grain storage, control is complicated and requires the fundamental pest management steps of bin sanitation, grain leveling, aeration, monitoring etc. These things are beyond this fact sheet.

In homes and restaurants, control is simpler.

Nonchemical control.

The first step in controlling pantry pests is to find and eliminate infested items. Often all that is needed to solve the problem is to remove an infested package of flour, macaroni, or cake mix. But finding the source of an infestation is not always easy. Infested packages are usually the oldest, most difficult to reach foods in the pantry. Even unopened containers may be infested; some pests can easily penetrate plastic, waxed paper, and cardboard containers. Before buying an item in the store, check that the bag or container is well sealed and undamaged.

Good sanitation is important. Infestations often start in pet foods, spilled grains, or other foods. Clean up spilled food promptly. Discard old packages of grain and pasta. Vacuum and clean pantry areas periodically to remove spilled foods. Remove and clean underneath shelf paper. Caulk around pantry edges and in cracks and crevices to reduce areas where spilled food may collect.

Most pantry pest problems can be prevented by using all dried food within 2 to 4 months of purchase. Spices and other products kept for longer periods should be sealed in airtight containers.

Pet food can be a special problem.  The most commonly infested pantry items are birdseed and dog and cat foods. Store pet foods in well-sealed plastic buckets or storage containers and use them promptly. Clean the containers thoroughly before refilling them with food.

Occasionally, mice or other rodents can cause a persistent beetle infestation. Hoarded seed and grain in abandoned rodent nests can support a small population of pests. Old rodent bait that contains grain also can harbor insects. When controlling rodents, prevent insect problems by placing the bait where it can be retrieved and discarded after the rodents are controlled.

Heat or cold treatments can eliminate pests in some food items such as pet food, bulk grains and beans, and home-grown dried beans or peas. Put the product in the oven at 130 degrees F for 1 hour, or in the freezer for 7 to 14 days. To prevent an infestation, store foods that may attract pantry pests in the refrigerator or freezer.

Chemical control

On rare occasions, insecticides may be needed to control difficult infestations. Insecticides can reach inaccessible areas that cannot be easily cleaned; they can also help reduce heavy pest infestations more quickly.

Insecticide sprays may be applied to crevices and void areas around cupboards, drawers, and pantries. Before spraying, remove all food products, utensils, and containers from the treatment area. Allow the spray to dry before placing clean shelf paper on the shelves and returning food, utensils, or containers to the pantry.

Insecticide products that are labeled for use in food- storage areas generally contain ingredients that are short-lived and relatively safe to use in the home. Active ingredients of these products include pyrethrins, resmethrin, allethrin, and tetramethrin.

For areas where long-term residual control is de- sired, look for products containing synthetic pyrethroids, such as permethrin, esfenvalerate, cyfluthrin, or bifenthrin. Aerosol fog products can temporarily suppress infestations of flying insects, but these fogs will not kill pantry pests in food containers or protected locations.

Before using an insecticide, always make sure that the label says that the product may be used indoors and in kitchens. Never spray food, dishes, utensils, or cooking items with pesticides.

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