   Centipedes - September 8, 2004 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Centipedes are sometimes confused with millipedes but can be differentiated by the number of legs per body segment. Centipedes have only one pair of legs per segment while millipedes can have two or four pairs of legs per segment. Yavapai County Cooperative Extension receives several calls per year about centipedes. Two species of centipede are common in north central Arizona. This column will discuss both of them and what to do when they are encountered. Centipedes are often reported to be vicious and almost a foot long. In truth, they are not vicious (unless they are being harassed) but one species is often 6 inches in length (they can reach 8½ inches). This large species is the giant desert centipede (Scolopendra heros) which occurs across much of Arizona and the southwest. Yes, they are scary looking, but try to get over it. They are beneficial, predatory members of our local ecosystems. While centipedes deserve your respect, they should not be handled. The giant desert centipede is often colored reddish-yellow with darker bluish-black stripes running horizontally across where each body segment joins the next. The head is usually red-orange with antennae and the last segment has a pair of legs is often mistaken for “stingers”. These are actually prehensile legs that the centipede uses for grasping objects or seizing its prey. On the first segment behind the head, the centipede has hollow tubes, with openings at their sharpened tips that function as fangs. They are attached to venom glands, and are used to kill prey. These fangs are sharp and could potentially penetrate leather gloves. The centipede's bite is considered about as serious as a bee sting, but the risk of secondary infection from other pathogens is also important to consider. Giant desert centipedes can also reportedly harm a person with the sharp claws of its many walking legs. Each walking leg is tipped with a sharp claw capable of making tiny cuts in human skin. A poison produced from the attachment point of each leg may be dropped into the wounds resulting in an inflamed and irritated condition. Now you can understand why they should never be handled. Centipedes are very fast and can slip through very small openings under doors, windows, and cracks. The best way to prevent them from entering your home is to maintain screens and weather stripping around windows and doors. You should also caulk any visible cracks. When working (especially around firewood, rocks, etc.), wear gloves and be cautious. Centipedes are nocturnal predators and remain hidden during the day. Around my house, I often find them in moist places where crickets and other prey seek refuge and below lights where moths and other prey insects congregate. Another species commonly found in our area is the house centipede (Scutigera coleoptrata). This species originally came from Mexico, but now can be found throughout the United States. It prefers damp areas and is usually seen in showers and bathtubs. It has fewer legs than the giant desert centipede, but its legs and antennae are longer in proportion to its body. It is also nocturnal and venomous. While it may offer some “natural” insect control in the home, most people find them disgusting and stomp them on site. Some sources recommend insecticides to control centipedes in and around the home. I prefer to recommend exclusion (as noted above) and then simple mechanical control (crushing or stomping) when they are found indoors. Another consideration is to control other insect populations within your home. Centipedes commonly eat roaches and crickets. By controlling these insects, you should decrease the incidence of centipedes in your home. I would tell you to relocate giant desert centipedes outdoors, but they are fast, venomous, and pose potential risks to health. It is best not put your self at risk by handing them. The University of Arizona Cooperative Extension has publications and information on gardening and pest management. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. |