A labama A & M and A uburn U ni v ersities The Brown

ANR-1043 Recluse

eople are often afraid of contrast, the orb-weaving garden Pspiders because of their spider has a symmetrical web. The ill-deserved reputation for enven- strands of the recluse’s webs are omizing victims. In fact, most white to off-white in color. do not have mouthparts strong enough to penetrate skin. Life Cycle Spiders are considered beneficial The average egg sac is about because they often 1⁄3-inch in diameter, and each sac prey on insects that we consider contains an average of 40 eggs. nuisances. Homeowners should The brown recluse female can leave spiders alone if the spiders Figure 1. with violin shape on cephalothorax and arrange- produce up to 300 eggs in her are in their natural habitat such as ment of six eyes (arrow). lifetime. Egg sacs are produced the yard or garden. However, the during summer, and the female brown recluse, Loxosceles reclusa, Distribution, Habitat, spider will guard the egg sac is an exception. until the spiderlings emerge. and Habits Spiderlings emerge after an Description The brown recluse spider incubation period of 24 to 36 The brown recluse spider has been collected throughout days and take between 10 to 12 belongs to a group of spiders Alabama but is more commonly months to develop into adults. commonly known as the “fiddle- found in the northern half of back” spiders because of the the state. It is commonly found The Bite indoors in storage areas such as violin-shaped marking they have Bites occur year-round on their cephalothorax (fused closets, basements, and cellars. The spiders take shelter in boxes, in heated homes where the head and thorax) (Figure 1). The temperature remains constant. shape and intensity of the fiddle stored clothing, shoes, under furniture, folded bedding, and in When a brown recluse bites, it design may vary. A more constant injects cytotoxins that cause tissue characteristic for identification is any other areas of clutter where it is dry and warm. death or of the bitten the number and pattern of the area (Figure 2). Many brown Brown recluse spiders are eyes. Most spiders have four pairs recluse spider bites go unnoticed adaptable. They are active in of eyes. The brown recluse has initially or result in mild stinging. temperatures ranging between only three pairs of eyes, arranged Some people may feel a burning 45°F and 110°F, can survive long in a semicircle on the front of the sensation within 30 minutes after cephalothorax (Figure 1). periods without food or water, These spiders are pale tan to and may live for up to 2 years. brown in color. Female bodies They generally are not aggressive. range in size from 10 to 15 mm Humans are usually bitten when (about 1⁄4 to 1⁄2 inch) andARCHIVE have a they inadvertently roll onto a leg span of over 25 mm (1 inch). spider during their sleep or put Males are generally half the size their foot in a seldom worn shoe of females. inhabited by a brown recluse. The Web The web of a brown recluse Figure 2. Serious reaction to a brown spider is irregularly constructed recluse . Three months after spi- with loose strands of silk. In der bite and skin graft.

www.aces.edu the bite. Then, within 8 hours, a prevent infection. Promptly seek Sanitation necrotic spot may develop which medical attention. If the spider can Remove any spiders found by can enlarge to the size of a silver be found, it should be collected vacuuming. Dispose of the bag dollar. If these symptoms do not and taken with the patient to the outside. Remove webs so that appear within 48 to 96 hours, doctor to confirm the identity of you can monitor potential spider necrosis is not likely. If these the spider involved. activity in future inspections. Sticky symptoms do appear, the area can Medical treatment may include boards placed along walls can also become ulcerated and sunken. the use of non-steroidal anti- be used for monitoring purposes. Lesions may take months to heal inflammatory drugs (NSAIDS) Professional pest control services (Figure 3). for inflammation and pain relief, can use flushing agents as a moni- antibiotics to prevent bacterial toring tool in an effort to locate infection, and treatments to breeding areas. prevent tetanus. Sulfone drugs The person conducting the may be prescribed. They have inspection should wear gloves. decreased the need to surgically To prevent spiders from crawling excise severe wounds in several up pant legs, constrict the pants studies. Other treatments may with rubber bands around the include early surgical excision of ankles. The person may even the wound and the use of cortico- consider wearing a bee veil when steroids and steroids. inspecting severely infested homes to prevent spiders from dropping Control on him or her. Figure 3. A more typical brown recluse spider bite. Photo taken several weeks An Integrated Pest Management after the bite. Lesions are healing. (IPM) approach is the best means Exclusion In rare instances, the reaction of control. IPM incorporates all Seal cracks and crevices in the can become systemic in as soon available control methods into a structure where spiders can enter as 6 hours. A systemic reaction pest management program. Control the home. Common areas for is characterized by fever, severe methods include sanitation, exclu- cracks and crevices are window abdominal pain, chest pain, sion, and chemical techniques. IPM sills, door thresholds, and around nausea, and vomiting. The majority includes doing a thorough inspec- pipes. Outdoors, eliminate potential of fatalities due to brown recluse tion of the premises to locate and breeding habitats such as wood bites are in children under the age destroy all brown recluse spiders piles, leaf litter, and rocks where of seven. Death is an extremely inside buildings. spiders may live near your house. rare occurrence. Control of the brown recluse spider is critical. Due to the Chemicals Treatment possible medical problems caused Use of pesticides labeled for by bites, a professional pest spider control is warranted for First aid for someone who has control service should be enlisted serious brown recluse infestations. been bitten by a brown recluse for severe infestations in the Spot treating corners or cracks spider includes use of an ice house. Until the brown recluse is and crevices in a house with a pack to prevent or to reduce the completely controlled in a home, pyrethroid pesticide, and treating swelling in the area where the bite occupants should carefully check crawl spaces with a dust formula- occurred. Cooling the area helps and shake out their bedding tion are some techniques available. to lessen tissue damage. Also, before going to sleep. Bites are Enlisting the services of a profes- sanitizing the area with hydrogen often inflicted when someone sional pest control operator is an peroxide or alcohol helps to rolls onto one during their sleep. option to be seriously considered Bed skirts should also be removed for brown recluse infestations. ARCHIVEto reduce the chances of spiders crawling onto the bed. Xing Ping Hu, Extension Entomologist, Associate Professor, Entomology and Plant Pathology, Auburn University. Originally prepared by Faith M. Oi, former Extension Entomologist, and Gary R. Mullen, Professor, both in Entomology and Plant Pathology at Auburn University. For more information, call your county Extension office. Look in your telephone directory under your county’s name to find the number. Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department of Agriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, reli- ANR-1043 gion, sex, age, veteran status, or disability. 6M, Reprinted March 2008, ANR-1043 © 2008 by the Alabama Cooperative Extension System. All rights reserved.